Electrical circuit for delivering power to consumer electronic devices

ABSTRACT

An electrical circuit for providing electrical power for use in powering electronic devices is described herein. The electrical circuit includes a primary power circuit and a secondary power circuit. The primary power circuit receives an alternating current (AC) input power signal from an electrical power source and generates an intermediate direct current (DC) power signal. The intermediate DC power signal is generated at a first voltage level that is less than a voltage level of the AC input power signal. The secondary power circuit receives the intermediate DC power signal from the primary power circuit and delivers an output DC power signal to an electronic device. The output DC power signal is delivered at an output voltage level that is less than the first voltage level of the intermediate DC power signal.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationSer. No. 62/069,672, filed on Oct. 28, 2014, claims priority to U.S.Provisional Patent Application Ser. No. 61/949,171, filed on Mar. 6,2014, and claims priority to U.S. Provisional Patent Application Ser.No. 61/896,557, filed on Oct. 28, 2013, all of which are herebyincorporated by reference in their entirety for all purposes.

FIELD OF THE INVENTION

The present invention relates generally to electrical power circuitsand, more particularly, to an electrical power circuit for providingelectrical power for use in charging and/or powering consumer electronicdevices.

BACKGROUND OF THE INVENTION

The Energy Crises Requires Demand Side Response That Lowers CurrentLoads. The Energy Crisis is upon us worldwide. For instance, the U.S.Department of Energy predicts that by 2015 there will not, on theaverage, be enough electric power to supply average demand in the U.S.

One of the controllable offenders is “Vampire Loads”. Also called “WallWart Power” or “Standby Power”, this electricity waste is estimated bythe U.S. Department of Energy (DOE) to be in excess of 100 Billion kWannually, costing over Ten Billion Dollars in wasted energy. VampireLoad producers includes cell phone chargers, lap top chargers, notebookchargers, calculator chargers, small appliances, and other batterypowered consumer devices.

The U.S. Department of Energy said in 2008:

“Many appliances continue to draw a small amount of power when they areswitched off. These “phantom” loads occur in most appliances that useelectricity, such as VCRs, televisions, stereos, computers, and kitchenappliances. This can be avoided by unplugging the appliance or using apower strip and using the switch on the power strip to cut all power tothe appliance.”

According to the U.S. Department of Energy, the following types ofdevices consume standby power:

-   -   1. Transformers for voltage conversion. (Including cell phone,        lap top and notepad, calculators and other battery powered        devices that use wall chargers).    -   2. Wall wart power supplies powering devices which are switched        off. (Including cell phone, lap top and notepad, calculator,        battery powered drills and tools, all of which have wall        chargers and have either completely charged the batteries or are        actually disconnected from the device).    -   3. Many devices with “instant-on” functions which respond        immediately to user action without warm-up delay.    -   4. Electronic and electrical devices in standby mode which can        be awakened by a remote control, e.g. some air conditioners,        audio-visual equipment such as a television receiver.    -   5. Electronic and electrical device which can carry out some        functions even when switched off, e.g. with an electrically        powered timer. Most modern computers consume standby power,        allowing them to be awakened remotely (by Wake on LAN, etc.) or        at a specified time. These functions are always enabled even if        not needed; power can be saved by disconnecting from mains        (sometimes by a switch on the back), but only if functionality        is not needed.    -   6. Uninterruptible power supplies (UPS)

All this means that even when a cell phone, lap top or like device iscompletely charged, current is still flowing, but not accomplishinganything and wasting electricity. More recently manufactured devices andappliances continue to draw current all day, every day—and cost youmoney and add to the Energy Crisis Worldwide.

The National Institute of Standards and Technology (NIST) (a division ofthe U.S. Department of Commerce) through its Buildings TechnologyResearch and Development Subcommittee in 2010 stated its goals forreducing “plug loads,” stating:

“The impact of plug loads on overall consumption is quite significant.For commercial buildings, plug loads are estimated at 35% of totalenergy use, for residential 25%, and for schools 10%.

Opportunities for lowering plug loads include:

-   -   1) more efficient plugged devices and appliances,    -   2) automated switching devices that turn off unused appliances        and reduce “vampire” loads from transformers and other small but        always on appliances, or    -   3) modifying occupant behaviors.”

One of the problems experienced by virtually all modern electronics isthat power supplies, whether external or embedded “power modules”, arenot energy efficient. This is true for a number of reasons, one of whichdates back to 1831 when Michael Faraday invented the transformer.Transformers are inherently inefficient because, as an analog device,they can only produce one power output for each specific winding. So iftwo power outputs are necessary, two secondary windings are necessary.Moreover, there are often over 50 parts and pieces that are necessary towork with a transformer to create a common modern external power supply,the numbers only get somewhat lower with internal or embedded powermodules. The number of parts in a power supply is inherently inefficientbecause current must travel in, around and through the various parts,each with different power dissipation factors; and even the circuittraces cause resistive losses creating energy waste.

Further, the way a transformer works is creating and collapsing amagnetic field. Since all of the electrons cannot be “recaptured” by themagnetic field creation/collapse, those that escape often do so as heat,which is why cell phone, lap top and tablet chargers feel warm or hot tothe touch. It is also the primary reason why all consumer electronicscreate heat, which not only wastes energy/electricity, but causeseventual detrition through heating of other associated electronic parts.

Another inefficiency found in current electronics is the need formultiple internal power supplies to run the different parts. Forinstance, in the modern world power modules, MOSFETS have become a moreand more important part of the “real world” interfaces in circuitry.

Metal-oxide-semiconductor field-effect transistors (MOSFETs) enableswitching, motor/solenoid driving, transformer interfacing, and a hostof other functions. At the other end of the spectrum is themicroprocessor. Microprocessors are characterized by steady reducedoperating voltages and currents, which may be 5 volts, 3.3 volts, 2.7volts or even 1.5 volts. In most systems the MOSFETS and microprocessorsare used together or in combination to make the circuitry work. However,most often the microprocessor and the drivers for the MOSFETS operate atdifferent voltages, causing the need for multiple power supplies withina circuit.

A standard high-voltage NMOS MOSFET requires a driver that can deliver agate voltage of 5-20 volts to successfully turn it on and off. In thecase of turn on, there is actually a requirement that the gate drivervoltage exceed the rail power to be effective. Specialty drivers usingcharge pump technology have been devised for this purpose. The othermain function of the high-voltage MOSFET gate driver is to have areduced input drive requirement making it compatible with the outputdrive capability of modern CMOS processor.

This MOSFET/driver arrangement, common in most external power supplies,like chargers, actually requires three separate power supplies. Thefirst power supply needed is the main power rail, which is normallycomposed of the rectified Line voltage in the range of 127 VDC to 375VDC supplied to the MOSFET. The second power supply needed is the 15volts (or higher) required by the MOSFET drivers. Finally, themicroprocessors require another isolated power supply for their manydifferent and varying voltages.

A good example of the current inefficiencies and energy waste is foundin a typical television, which requires as many as four to six differentpower supply modules to run the screen, backlighting, main circuitboard, and sound and auxiliary boards. This current system requiresmultiple transformers and dozens of parts for each power supply needed.The transformers and the parts (including MOSFETS) multiply heat throughtheir duplicated inefficiencies, which is one reason the back of atelevision is always hot to the touch. In addition, the moretransformers that are needed for various power outputs, the more partsare needed, and more causation for energy waste is created.

In addition to the heat problem, the multiple transformer based powersupplies all need typically from forty to sixty parts to operate,requiring dozens of parts for a typical transformerbased televisionpower supply module which increases costs and total component size whiledecreasing reliability. With the multiplicity of parts comes increasedsystem resistance which ends up in wasted energy as heat.

The present invention is aimed at one or more of the problems identifiedabove to provide better efficiencies and create more control overelectrical inrush currents from rail sources.

SUMMARY OF THE INVENTION

In one aspect of the present invention, an electrical circuit forproviding electrical power for use in charging applications and/orpowering a constant supply circuit for electronic devices is provided.The electrical circuit includes a primary power circuit that is adaptedto be electrically coupled to an electrical power source, and asecondary power circuit that is electrically coupled to the primarypower circuit. The primary power circuit is configured to receive analternating current (AC) input power signal from the electrical powersource and generate an intermediate direct current (DC) power signal. Inthe AC input case, the intermediate DC power signal is generated at afirst voltage level that is less than the voltage level of the AC inputpower signal. The secondary power circuit is configured to receive theintermediate DC power signal from the primary power circuit and deliveran output DC power signal to an electronic device. The output DC powersignal is delivered at an output voltage level that is less than thefirst voltage level of the intermediate DC power signal.

In another aspect of the present invention, a power module for providingelectrical power for use in powering electronic devices, like monitors,televisions, white goods, data centers, and telecom circuit boards, isprovided. The power module includes a rectifier circuit, a switchcapacitor voltage breakdown circuit and controller integrated circuit,and a forward converter circuit. The rectifier circuit receives an ACpower input signal from an electrical power source and generates arectified DC power signal. The switch capacitor voltage breakdowncircuit and controller integrated circuit receives the rectified DCpower signal and generates an intermediate DC power signal based upon anintegrated controller which senses the voltage level of the AC powerinput signal and adjusts the gain of the switch capacitor voltagebreakdown circuit as a function of the sensed voltage level. The forwardconverter circuit includes a transformer that receives the intermediateDC power signal and generates an output DC power signal that isdelivered to the electronic device.

In a further aspect of the present invention, a high-efficiency switchcapacitor voltage breakdown circuit for AC-DC and DC-DC conversion isprovided. The high-efficiency switch capacitor voltage breakdown circuitincludes a pair of flyback capacitors electrically coupled in parallel,and a plurality of switch assemblies that are electrically coupled toeach of the pair of flyback capacitors. In one embodiment, the gatesbetween the capacitors are shared. The switch assemblies may be operatedto selectively deliver an input DC power signal to each of the pair offlyback capacitors during a charge phase, and to selectively deliver anoutput DC power signal to an electronic device during a discharge phasethat has a lower voltage level than the input DC power signal. At leastone switch assembly may include an N-channel MOSFET switch and a levelshifter for delivering a control signal to the N-channel MOSFET switch.In addition, a dickson charge pump may be coupled to the level shifterto receive the input DC power signal and generate an output power signalhaving a higher voltage level than the input DC signal. The output powersignal is delivered to the level shifter for use in operating N-channelMOSFET switch (or closing for other types of MOSFETs). In addition, theswitch capacitor voltage breakdown circuit may include a control circuitthat includes a voltage sensing circuit for sensing a voltage level ofthe input DC power signal and a gain controller configured to select again setting of the switch capacitor voltage breakdown circuit as afunction of the sensed voltage level and operate each of the pluralityof switch assemblies as a function of the selected gain setting.

The electrical circuit may also includes a vampire load eliminationsystem that is configured to determine when a consumer device hasfinished charging and/or is disconnected from the power circuit, andoperates the power circuit to disconnect the supply of power to thepower circuit and/or the electronic device, and also capable of creatinga flea powered “stand-by” mode.

In another aspect of the invention, the power circuit is formed on asemiconductor chip that includes analog and digital components on thesame chip. A semiconductor process such as a 350V Silicon-on-Insulator(SoI) BCD process could be used for the semiconductor, which wouldpermit the integration on one die of the microcontroller, timer/quartzreal-time clock, PID controller and PWM controllers, MOSFETs, andcorresponding drivers. In addition, the typical specific capacitance inCMOS technology ranges from 0.1 fF/μm2 (polypoly capacitors) to 5 fF/μm2(MIM capacitors) or ceramic capacitors can be considered. Moreover, aprocess like DMOS can be used, or a bi/substrate can be considered, suchas a layer of Silicon Carbonate, with Gallium Nitrate or Silicon Dioxidebi/substrata's also can be used. Or alternatively, Gallium Nitrate orGallium Arsenide and the use of Deep Trench capacitors could be used forconstruction of the chip rather than silicon. All of these options arenecessary because of the capacitance needed with the low R_(on) MOSFETSor transistors.

A BCDMOS process may be used to manufacture the power circuit. BCDMOSincludes a process for integrating Bipolar (analog), CMOS (logic) andDMOS (power) functions on a single chip for ultra high voltage (UHV)applications. BCDMOS provides a broad range of UHV applications such asLED lighting, AC-DC conversion and switched mode power supplies. Capableof operating directly “off line” from a 110/220 VAC source, integratedcircuits (ICs) implemented with a non-Epi process can deploy optimized450V/700V DR-LDMOS transistors that specify low on resistance and abreakdown voltage that exceeds 750V. When used in power switchingapplications, designers can expect lower conduction and switchinglosses.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages of the present invention will be readily appreciated asthe same becomes better understood by reference to the followingdetailed description when considered in connection with the accompanyingdrawings wherein:

FIG. 1 is a schematic diagram of an electronic charging device for usein providing electrical power to electronic devices, according to anembodiment of the present invention;

FIG. 2 is a block diagram of a power circuit that may be used with thecharging device shown in FIG. 1, for use in providing electrical powerto electronic devices, according to an embodiment of the presentinvention;

FIG. 3 is a schematic diagram of a buck regulator circuit that may beused with the power circuit creating a “Hybrid” voltage break-downcircuit as shown in FIG. 2, according to an embodiment of the presentinvention;

FIGS. 4-7 are schematic diagrams of a switch capacitor voltage breakdowncircuit that may be used with the power circuit shown in FIG. 2,including the sharing of gates between capacitors for further reducingRDS_(ON) losses, according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of a portion of the switch capacitorvoltage breakdown circuit shown in FIG. 4, according to an embodiment ofthe present invention;

FIG. 9 is a table illustrating gain settings for use with the switchcapacitor voltage breakdown circuit shown in FIG. 8, according to anembodiment of the present invention;

FIGS. 10-12 are schematic illustrations of the switch capacitor voltagebreakdown circuit shown in FIG. 8 in a charge phase mode and a dischargephase mode associated with each of the gain settings shown in FIG. 9,according to an embodiment of the present invention;

FIG. 13 is a schematic diagram of a forward converter circuit that maybe used with the power circuit shown in FIG. 2, according to anembodiment of the present invention;

FIG. 14 is a schematic diagram of an alarm control circuit that may beused with the power circuit shown in FIG. 2, according to an embodimentof the present invention;

FIG. 15 is another schematic diagram of the power circuit shown in FIG.2, including a power controller integrated circuit, according to anembodiment of the present invention;

FIGS. 16, 17A, and 17B are block diagrams of the power controllerintegrated circuit shown in FIG. 10, according to embodiments of thepresent invention;

FIG. 18 is a block diagram of a power management unit that may be usedwith the power controller integrated circuit shown in FIGS. 16, 17A, and17B, according to an embodiment of the present invention;

FIG. 19 is a graphic illustration of Power-On-Reset threshold voltagesthat may be used with the power controller integrated circuit shown inFIGS. 16, 17A, and 17B;

FIG. 20 is a schematic illustration of a Proportional to Integral andDifferential Regulator Control circuit that may be used with the powercontroller integrated circuit shown in FIGS. 16, 17A, and 17B, accordingto an embodiment of the present invention;

FIGS. 21 and 22 are block diagrams of a digital control block that maybe used with the power controller integrated circuit shown in FIGS. 16,17A, and 17B, according to embodiments of the present invention;

FIG. 23 is a flow chart illustrating a method of operating the powercircuit shown in FIG. 2 for use in providing electrical power toelectronic devices, according to an embodiment of the present invention;

FIG. 24 is a graphic illustration of state transitions that may be usedwith the method shown in FIG. 23, according to an embodiment of thepresent invention;

FIG. 25 is a schematic illustration of a communication interface thatmay be used with the power controller integrated circuit shown in FIGS.16, 17A, and 17B, according to an embodiment of the present invention;

FIG. 26 is a schematic illustration of a microprocessor communicationprotocol that may be used with the power controller integrated circuitshown in FIGS. 16, 17A, and 17B, according to an embodiment of thepresent invention;

FIG. 27 is a schematic illustration of an Inter-Integrated Circuit thatmay be used with the power controller integrated circuit shown in FIGS.16, 17A, and 17B, according to an embodiment of the present invention;

FIGS. 28 and 29 are schematic illustrations of the power circuit shownin FIG. 2, according to an embodiment of the present invention;

FIG. 30 is a connection diagram that may be used with the powercontroller integrated circuit shown in FIGS. 16, 17A, and 17B, accordingto an embodiment of the present invention;

FIGS. 31 and 32 are additional schematic illustrations of the powercontroller integrated circuit shown in FIGS. 16, 17A, and 17B, accordingto embodiments of the present invention;

FIG. 33 is a flow chart of an algorithm for a low-current detection andan error detection that may be used with the power controller integratedcircuit shown in FIGS. 16, 17A, and 17B, according to an embodiment ofthe present invention;

FIGS. 34 and 35 are schematic illustrations of the power circuit shownin FIG. 2, according to an embodiment of the present invention;

FIG. 36 is a schematic illustration of Level Shifter that may be usedwith the power circuit shown in FIG. 2, according to an embodiment ofthe present invention;

FIG. 37 is a schematic illustration of an RCD circuit that may be usedwith the forward converter circuit shown in FIG. 13, according to anembodiment of the present invention;

FIGS. 38 and 39 are additional schematic illustrations of the powercircuit shown in FIG. 2, according to an embodiment of the presentinvention;

FIG. 40 is a schematic illustration of a portion of the power circuitshown in FIG. 2, according to an embodiment of the present invention;and,

FIG. 41 is another schematic illustrations of the power circuit shown inFIG. 2, according to an embodiment of the present invention.

Corresponding reference characters indicate corresponding partsthroughout the drawings.

DETAILED DESCRIPTION OF INVENTION

With reference to the drawings and in operation, the present inventionovercomes at least some of the disadvantages of known power deliverysystems by providing a power module that includes a power circuit thatprovides DC voltage output power to consumer electronic devices from anAC mains supply (typically 120 VAC (US) to 240 VAC[EU/Asia]). The powercircuit is configured to provide electrical power to charge electronicstorage devices and/or power consumer electronic products including, butnot limited to, a cell phone, a smartphone, a tablet computer, a laptop,and/or any suitable electronic device that may benefit from thisinvention due to extremely high efficiencies and very low stand-by powerrequirements. In general, the power circuit includes a primary powercircuit and a secondary power circuit for receiving high voltage ACpower from an electrical power source and delivering a low voltage DCpower signal to one or more electronic devices. The primary powercircuit receives the AC power signal from an AC power supply andgenerates an intermediate direct current (DC) power signal at a reducedvoltage level. The secondary power circuit receives the intermediate DCpower signal from the primary power circuit and generates and deliversan output DC power signal having a voltage level suitable for use inpowering and/or charging consumer electronic devices.

The primary power circuit includes a rectification circuit for receivingthe AC power signal and generating a rectified DC power signal, and aswitch capacitor voltage breakdown circuit for dividing the rectified DCvoltage to a reduced voltage for use by the secondary power circuit. Theswitch capacitor voltage breakdown circuit includes fly-back capacitorsto maximize power efficiency and a hold capacitor to minimize thevoltage ripple. In one embodiment, the switch capacitor voltagebreakdown circuit is configured to deliver up to 50 mA and maintain ≧95%efficiency across the range of load currents from 50 mA to less than 1mA under light load conditions. The primary power circuit may alsoinclude a switch-mode buck regulator that is connected in parallel withthe switch capacitor voltage breakdown circuit for handling largecurrent loads, for example, up to 430 mA of current. The buck regulatormay include a P-channel MOSFET switch, a high voltage buck diode, and abuck energy storage inductor. In addition, the buck regulator may alsoinclude a pulse-width modulator (PWM) controller for generating a pulsewidth modulated signal to control the on/off time of the buck regulatorPMOSFET, which may also be expressed as an NMOSFET with the appropriategate drivers.

The secondary power circuit includes a forward converter power circuitthat includes a transformer for receiving the intermediate DC powersignal from the primary power circuit and generating the output DC powersignal. The forward converter also includes a MOSFET connected to theprimary side of the transformer and a control circuit to operate theMOSFET to regulate the voltage at the output of the forward converter asload current is drawn from the secondary-side of the transformer. Forexample, the forward converter control loop may be configured toregulate the output voltage under heavy fluctuation (4.5 nA to 4.5 A) ofload current without triggering any instability.

In the modern world, the MOSFET has become a more and more importantpart of “Real World” interfaces. It enables motor/solenoid driving,transformer interfacing, and a host of other functions. At the other endof the spectrum is the Microprocessor. It is characterized by steadilyreduced operating voltages and currents. In many systems these parts areused together. A standard high-voltage MOSFET requires a driver that candeliver on the order of a 5 v to 20 v volt swing to the FET gate inorder to successfully turn the FET on or off. In the case of turn-on foran NMOSFET, it is actually required that this gate drive voltage exceedthe power rail voltage. Specialty drivers using charge pump technologyhave been devised for this purpose, but they are typically discreteparts and increase the number of power rails needed on a circuit. TheFET driver's other main function is to have a reduced input voltagerequirement making it compatible with the output port capability of amodern CMOS microprocessor. This arrangement is costly in terms of powerand typically requires three power supplies. First is the main powerrail. It is composed of a voltage in the range of 100 to 600 voltssupplied to the MOSFET. The second supply is the 5-20 volts required bythe driver and finally is the supply required by the microprocessor.This present invention combines all these rails within the chip, suchthat the power and parts normally associated with the circuit areminimized and therefore efficiencies increased.

In many circumstances, the power supplies constitute a significantpercentage of both the parts count and cost in a small system. Aconsolidated part can substantially alter this equation. This new partwould consist of a combination of a high power MOSFET as the base partto which is added the appropriate driver with an included charge pump.Also added is the power supply required for the driver derived from themain rail supply internally. A final addition is an output pin to supplypower for the microprocessor from this internal supply. In many modestsystems the complete parts list would consist of this new device, themicroprocessor, and the main power rail parts. This would allow the nextgeneration of low cost/low assembly count microprocessor subsystems.

The power module includes the advanced power supply system on a chip(Tronium PSSoC), which is the subject of this present invention,including a controller application specific integrated circuit (ASIC) toprovide a low-cost, highly efficient means to convert the AC linevoltage present at a typical home or business electrical outlet to areduced regulated DC voltage for consumer electronic applications.Typical applications include, but are not limited to, charging systemsfor cell-phones, tablets or other handheld devices, USB powerconversion, power supplies for consumer, medical and industrial devices,and many other possible uses.

The Tronium PSSoC is configured for use in two primary power moduleapplications including an Autonomous Power Module and a Universal PowerModule. The Autonomous Power Module operates in an autonomous mode ofoperation that is based upon an analog feedback approach for reducedcost. The Universal Power Module operates in a universal mode ofoperation that utilizes a microprocessor (μP) controller to providefeedback for regulation of the final output voltage, which can be onepower rail which is controlled/monitored or more. Some key features ofthe Tronium PSSoC include, but are not limited to, 90 VAC to 264 VACLine Voltage Operation (other input voltage either AC or DC may beused), Programmable Output Voltage, Hybrid switch capacitor voltagebreakdown circuit & Switch-Mode Buck Regulator (which is synchronouslyrectified for efficiency) for DC-DC Conversion, PID Regulation ControlLoop for High Accuracy, Digital State Machines for Current andTemperature Monitoring, Ultra-Low Power Dissipation for Idle (Vampire)Mode of Operation, Opto-Isolated Microprocessor Interface forConfiguration and Control, I2C Slave Port for Manufacturing Test,auto-detect input voltage range: 127 VDC to 373 VDC (world-wide voltages110 VAC-260 VAC), featured Out Power: 22.5 W (any wattage possible),hybrid voltage converter for high-efficiency operation, stacked SwitchCapacitor Voltage Breakdown Modules, PID regulation loops with PWM gatedrivers, power scaling function for high efficiency at multiple loadlevels and flea power Stand-by Mode, thermal sensing and shut-off, shortcircuit and over-current protection, adjustable no-load/light loadshut-off with restart and control logic, selectable analog or digitalcontrol, minimal or no external circuitry part count and discrete devicesize, and optional digital interface for bi-directional communication.

In addition, the Switch Mode Buck Regulator circuit may include a whatis typically know as a Buck/Boost circuit; or the Buck/Boost may bereplaced with a SEPIC, Cúk, or Push Pull or other topologies. These willhave synchronous rectification for efficiency and may either use afly-back or forward convertor typologies.

The Tronium PSSoC is an advanced power controller integrated circuitthat is configured to provide output voltage regulation withhigh-efficiency and high accuracy. The advanced features of the TroniumPSSoC provide the user with a multi-purpose device which can be used ina large variety of applications in either a “charger” mode or “constantsupply” mode. Programmable output voltages (1.7V to 48V or higher) arepossible with the Tronium PSSoC, with little or no loss of efficiencyacross a variety of current load conditions, which feature is called the“Dial-a-Voltage” feature. In addition, multiple output currents may becreated by the combination of the Hybrid Circuit, or the SwitchCapacitor Circuit by itself, so as to create multiple voltage/currentcombinations ranging typically from 1.7V to 48V, which is sufficient topower most electronic devices. This “Dial-a-Voltage” feature, is factoryprogrammable or programmable by a customer with a proper code, so thatthe same chip may be used for a 1.7V output or a 48V output, with onlynominal changes in any external components like the transformer windingand the FETs which drives the transformer.

The Tronium Power Supply System on a Chip (PSSoC) ASIC is an advancedpower control device that enables high efficiencies across a very widerange of output power. While typical ‘high efficiency’ power supplycontrollers boast ˜50% efficiencies down to 10% of full load, theTronium device is intended to provide >90% efficiency down to and below1% of full load.

The Tronium PSSoC provides a revolutionary topology for high voltagepower conversion by implementing an intermediary voltage rail, allowingthe power capabilities of the system to scale with the load demand. Italso shrinks parts into the ASIC, minimizing external parts needed; andenables a wider range of transformer options for enhanced optimizationof power with lower coil losses. The Tronium PSSoC also provides a PIDswitching controller with which to drive the primary side of atransformer if isolation is required, or other topologies of conversionand regulation. It also features either secondary or primary sidecontrol/feedback.

In one embodiment, the Tronium PSSoC uses a proprietary high-voltageintermediate voltage capacitor voltage breakdown conversion scheme,which can be used alone, or in combination with a switch-mode buckregulator to maintain high-efficiency regardless of the load voltage orcurrent. When no current is being drawn by the load, the device willenter a low-current mode of operation of approximately ½ milliwatt inorder to minimize and virtually eliminate the traditional ‘vampire’current required to stay awake.

The Tronium PSSoC may include the following major circuit blocks:Intermediate Capacitor Voltage Break-Down Converter Module (CVBD Module)(can be one or more stages for desired current output); High-VoltageSingle-Stage or Two-Stage switch capacitor voltage breakdown circuit;Proportional to Integral and Differential (PID) Regulator Control Blockfor PWM Control of Forward Converter; Switch-Mode Buck Regulator PIDController (optional Hybrid typology for voltage output); Buck RegulatorSwitch Driver; Current and Temperature Sense Blocks; 12-bit ADC forVoltage and Current Monitoring; 10-bit DAC's for Feedback Control;Digital Control Block for Current Monitoring State Machine; Serial Inputfor Opto-Isolator Communications Interface; I2C Serial Interface Portfor Test, Evaluation, Repair and Communication; Oscillators forgeneration of internal clock signals; Power Manager for On-Chip Voltageand Current Generation; Adapted for use with or without amicrocontroller which can be embedded into the chip or external; PrimarySide Sensing or Secondary Side Sensing Capabilities; and Synchronousforward convertor.

The power module may also include a Tronium PSSoC that includes bothanalog and digital control in order to optimize performance andefficiency. In order to enable not only analog control but also digitalcontrol the proper inputs and outputs must be available on the TroniumPSSoC. Given these availabilities, and coupled with power loop controlfrom an internal clock—control of the clock can be driven and controlledwith external signals. The novel approach is that these signals can bedriven from the secondary side while the Tronium PSSoC sits on theprimary side of the transformer.

Digital control is commonly accomplished on the same side of theisolation barrier. However, given that the Tronium PSSoC is inherentlyan isolated system, and end to end efficiency optimization is required,control from primary side or secondary back to primary side may beutilized. This is accomplished in a number of different ways given theTronium implementation. This can be done with optocouplers transmittingthe digital control signal from a microcontroller as well as analogsignals from a current sense circuit. Furthermore, this can beaccomplished by using a third winding on the isolation transformer.

Some or all of the circuits and/or electrical devices include in thepower circuit may be integrated onto the chip using either a siliconprocess, Gallium nitride (GaN) or Gallium Arsenide (GaA), or by usingDeep Trench Capacitors, or other available processes which provides highefficiency parts, if high efficiency is desired. Thus, one or all ofthese parts may be embedded in the ASIC rather than be externaldiscretes, even the transformer, using the known transformer in silicon(or GaN—GaA) techniques. In addition, the use of MIM and MOM capacitorsalong with low RDS_(ON) MOSFETS, integrated decoupling capacitors and/orflying capacitors (C_(FLY)), for ripple reduction, which in turndecreases the size of needed capacitors may be used where capacitors orFETS are called for herein. Also, the introduction of integratedinductors on chip helps achieve the highest efficiencies. Alternatively,the highest efficiency parts, like GaA, GaN or Schottky diode parts areto be used.

In addition, the capacitors may be nano-capacitors, and may be basedupon ferroelectric and core-shell materials as well as those based onnanowires, nanopillars, nanotubes, and nanoporous materials.

The substrata for the Tronium PSSoC could be made from customary filmscurrently used in capacitors (if external) or within semiconductorsubstrates such as high or low Ohmic silicon substrate, polysilicon,gallium nitride, gallium arsenide, silicon germanium or substances likesilicon carbide or indium phosphide.

They key is on-board ASIC integration of as many discretes as possiblewhere the process permits, and if efficiency is key then identificationof low RDSon values, high efficient parts, and sufficient voltagebreak-down parts. Another key is to run the Switch Buck Module at higherfrequencies, so that parts become smaller, and sufficiently smaller tobecome on-board chip devices.

A selected embodiment of the present invention will now be explainedwith reference to the drawings. It will be apparent to those skilled inthe art from this disclosure that the following description of theembodiment of the present invention is provided for illustration onlyand not for the purpose of limiting the invention as defined by theappended claims and their equivalents.

FIG. 1 is a schematic diagram of an electronic charging device 10 foruse in providing electrical power to electronic devices. FIG. 2 is ablock diagram of a power module 12 that may be used with the electroniccharging device 10. In the illustrated embodiment, the electroniccharging device 10 includes a housing 14, a pair of power prongs 16extending outwardly from the housing 14 and a device connection assembly18 that is adapted to connect to an electronic device 20 to deliverelectric power from the charging device 10 to the electronic device. Theelectronic charging device 10 also includes the power module 12 thatincludes a power circuit 22 that is configured to receive power from anelectrical power source 24 and deliver power to the electronic device 20such as, for example, portable consumer electronic devices including,but not limited to, a cell phone, a smartphone, a tablet computer, alaptop, and/or any suitable electronic device. In addition, the powercircuit 22 may deliver power for use in charging electronic storagedevices such as, for example, mobile phone/laptop/tablet power storagebatteries. In one embodiment, the power circuit 22 may be configured toprovide low voltage DC output (typically 5 VDC) from an AC mains supplytypically 120 VAC (US) to 264 VAC[EU/Asia].

In the illustrated embodiment, the power circuit 22 includes a primarypower circuit 26 and a secondary power circuit 28. The primary powercircuit 26 is adapted to be electrically coupled to the electrical powersource 24 and is configured to receive an AC (or DC) input power signalfrom the electrical power source 24 and generate an intermediate directcurrent (DC) power signal. The intermediate DC power signal beinggenerated at a first voltage level that is less than a voltage level ofthe AC input power signal. The secondary power circuit 28 iselectrically coupled to the primary power circuit 26 and is configuredto receive the intermediate DC power signal from the primary powercircuit 26 and deliver an output DC power signal to the electronicdevice 20. The output DC power signal is delivered at an output voltagelevel that is less than the first voltage level of the intermediate DCpower signal. For example, in one embodiment, the primary power circuit26 is configured to receive the AC input signal having a voltage levelbetween a range of 127 volts to 375 volts AC and to deliver theintermediate DC power signal at a voltage level of approximately 110volts DC. The secondary power circuit 28 is configured to receive theintermediate DC power signal and deliver the output DC power signal atapproximately 5 volts DC.

In the illustrated AC-DC embodiment, the primary power circuit includesa rectifier circuit 30, an intermediate voltage converter 32, a buckregulator 34, and a hold capacitor 36 that is electrically coupled tothe intermediate voltage converter 32 and the buck regulator 34. Theintermediate voltage converter 32 and the buck regulator 34 are coupledin parallel between the rectifier circuit 30 and the secondary powercircuit 28. The rectifier circuit 30 is configured receive the AC powerinput signal from the electrical power source 24 and generate arectified DC power signal that is delivered to the intermediate voltageconverter 32 and the buck regulator 34. In one embodiment, the rectifiedDC power signal is delivered having a voltage level that isapproximately equal to the voltage level of the AC input power signal.As shown in FIGS. 13 and 15, in the illustrated embodiment, therectifier circuit 30 includes a plurality of diodes 38 that are arrangedin a full-wave bridge rectifier having first and second input terminalscoupled to the high and low sides of the electrical power source 24 forproducing a DC power signal from an AC input power signal. In oneembodiment, the rectifier circuit 30 may also include a filter capacitor40 that is coupled to the full-wave bridge rectifier. In yet anotherembodiment, the rectifier circuit 30 does not include the filtercapacitor 40. In another embodiment, the rectifier circuit 30 mayinclude a half-bridge rectifier (not shown).

FIG. 3 is a schematic diagram of the buck regulator circuit 34 that maybe used with the power circuit 22. In the illustrated embodiment, thebuck regulator circuit 34 includes a regulator switch assembly 42 thatis coupled to a voltage reduction circuit 44. The voltage reductioncircuit 44 includes a high voltage buck diode 46, a buck energy storageinductor 48, and a capacitor 50. The regulator switch assembly 42 isoperated to selectively deliver the rectified DC power signal to thevoltage reduction circuit 44. In the illustrated embodiment, theregulator switch assembly 42 includes a P-channel MOSFET 52, a drivercircuit 54 that is coupled to the P-channel MOSFET 52, and a levelshifter 56 that is coupled to the driver circuit 54. In one embodimentthe regulator switch assembly 42 may include an N-channel MOSFET and/ora P-channel MOSFET. In the illustrated embodiment, the buck regulator 34also includes a regulator control circuit 58 that includes a regulatorPWM controller 60 (also shown in FIGS. 16, 17A, and 17B) for generatinga pulse width modulated signal to control P-channel MOSFET 52. In oneembodiment, the control circuit 58 may also include a voltage sensingcircuit 62 that is connected to the primary side of the forwardconverter transformer for sensing the voltage level of the intermediateDC power signal being delivered to the secondary power circuit 28. Theregulator PWM controller 60 may generate a pulse-width modulated controlsignal as a function of the sensed first voltage level to adjust a dutycycle of the PWM control signal being delivered to the P-channel MOSFET52 to maintain the voltage level of the intermediate DC power signal.The Buck Regulator servo loop 58 is voltage controlled and the Vprimaryis sensed and used to modulate the duty cycle of the driver 54.

In one embodiment, the sensing circuit 62 includes one or more HallEffect sensors that are coupled to the primary side of the forwardconverter transformer for sensing a magnetic field being generatedwithin the transformer. The Hall Effect sensors facilitate determining azero-crossing of the transformer by directly sensing the magnetic fieldbeing generated by the transformer during operation. In one embodiment,the sensing circuit 62 includes a primary side Hall Effect sensorcoupled to the primary side of the transformer. The primary side HallEffect sensor is connected to the PWM controller 60 for transmitting asignal to the PWM controller 60 for use in determining when thetransformer nears the “zero-crossing”. In another embodiment, thesensing circuit 62 includes a secondary side Hall Effect sensor that iscoupled to the secondary side of the transformer, and is connected tothe forward converter controller (shown in FIG. 13) for transmitting asignal indicative of the transformer magnetic field for use indetermining the time at which the transformer reaches the“zero-crossing”.

FIGS. 4-8 are schematic diagrams of the intermediate voltage converter32. FIG. 9 is a table illustrating gain settings that may be used withthe intermediate voltage converter 32. FIGS. 10-12 are schematicillustrations of the intermediate voltage converter 32 in a charge phasemode 66 and a discharge phase mode 68 for each of the gain settingsshown in FIG. 9. In the illustrated embodiment, the intermediate voltageconverter 32 includes a single-stage switch capacitor voltage breakdowncircuit that is coupled to the hold capacitor 36 and the secondary powercircuit 28. The switch capacitor voltage breakdown circuit includes apair of flyback capacitors 70 that are electrically coupled in paralleland a plurality of switch assemblies 72 that are electrically coupled toeach of the flyback capacitors 70. The switch assemblies 72 areselectively operated between the charge phase mode 66 and the dischargephase mode 68. During the charge phase mode 66 the switch assemblies 72are operated to form a charging circuit 74 to connect the flybackcapacitors 70 to the rectifier circuit 30 to deliver the rectified DCpower signal to each of the flyback capacitors 70. During the dischargephase mode 68, the switch assemblies 72 are operated to form adischarging circuit 76 to connect the flyback capacitors 70 to thesecondary power circuit 28 to deliver the intermediate DC power signalto the hold capacitor 36.

In one embodiment, as shown in FIG. 8, the single-stage switch capacitorvoltage breakdown circuit 32 may include a first flyback capacitor Cfb1and a second flyback capacitor Cfb2, and nine switch assemblies S1, S2,S3, S4, S5, S6, S7, S8, and S9. In addition, two of the switchassemblies S3 and S9 are coupled to ground. During operation, the gainsetting of the switch capacitor voltage breakdown circuit may beadjusted by selectively operating the switch assemblies according to thegain setting table shown in FIG. 9. For example, during the charge phasemode 66 (Phase 1), switches S1, S4, S7, and S8 are turned on and movedto a closed position and switch assemblies S2, S3, S5, S6, and S9 areturned off and moved to an open position to form the charging circuit 74to connect the flyback capacitors Cfb1 and Cfb2 to the rectifier circuit30. As shown in FIG. 10-12, in the charging circuit 74 the top plate ofeach flyback capacitor Cfb1 and Cfb2 are connected to the rectifiercircuit 30 line voltage, Vline. For a gain setting equal to G=1x, duringthe discharge phase mode 68 (Phase 2), switch assemblies S2, S3, and S7are turned on and switch assemblies S1, S4, S5, S6, S8, and S9 areturned off to form a discharging circuit 76 shown in FIG. 10 thatincludes the top plate of capacitor Cfb1 connected to the hold capacitor36 and the top plate of capacitor Cfb2 connected to the bottom plate ofcapacitor Cfb1. With reference to FIGS. 9 and 11, for a gain settingequal to G=½x, during the discharge phase mode 68 (Phase 2), switchassemblies S2, S5, and S9 are turned on and switch assemblies S1, S3,S4, S6, S7 and S8 are turned off to form a discharging circuit 76 thatincludes the top plate of capacitor Cfb1 connected to the hold capacitor36, the bottom plate of capacitor Cfb1 connected to ground, and the topplate of capacitor Cfb2 connected to the hold capacitor 36, the bottomplate of capacitor Cfb2 connected to ground. Referring to FIGS. 9 and12, for example, a gain setting equal to G=⅔x, during the dischargephase mode 68 (Phase 2), switch assemblies S2, S6, and S9 are turned onand switch assemblies S1, S3, S4, S5, S7 and S8 are turned off to form adischarging circuit 76 that includes the top plate of capacitor Cfb1connected to the hold capacitor 36, top plate of capacitor Cfb2connected to the bottom plate of capacitor Cfb1, and bottom plate ofcapacitor Cfb2 connected to ground.

In one embodiment, multiple “stages” of the switch capacitor circuits,as explained herein, are linked together, which may be used to gainadditional current output, with or without the need for the addition ofthe Hybrid power conversion/regulation circuits.

Referring to FIG. 7, in the illustrated embodiment, the switch capacitorvoltage breakdown circuit 32 also includes a control circuit 78 that iscoupled to each of the switch assemblies 72 to operate the switchcapacitor voltage breakdown circuit 32. The control circuit 78 includesa voltage sensing circuit 80 for sensing a voltage level of therectified DC power signal being received from the rectifier circuit 30and a gain controller 82 that is configured to select a gain setting ofthe switch capacitor voltage breakdown circuit 32 as a function of thesensed voltage level and operate each of the plurality of switchassemblies as a function of the selected gain setting. By providing acontrol circuit 78 that selects the gain setting of the switch capacitorvoltage breakdown circuit 32 as a function of the sensed input voltagelevel, the switch capacitor voltage breakdown circuit 32 is able toadjust the operation of the switch capacitor voltage breakdown circuit32 to account for variations of AC voltage levels in different countriesand/or power grids and deliver the intermediate DC output signal at apredefined voltage level and maintain optimum power efficiency. In theillustrated embodiment, the control circuit 78 includes a resistordivider 84, a pair of comparators 86, a logic decoder 88, and a gaincontroller 82. The negative input of the comparators 86 is connected toa bandgap generator and the positive inputs are connected to therectifier circuit 30 line voltage, Vline.

Referring to FIGS. 4-6, in the illustrated embodiment, one or moreswitch assemblies includes an N-channel MOSFET switch 90, and a levelshifter 92 that is connected to the N-channel MOSFET switch 90 fordelivering a control signal to the N-channel MOSFET switch 90 tofacilitate operating the N-channel MOSFET 90. In addition, one or moreswitch assemblies 72 include a Dickson charge pump 94 that is connectedto the level shifter 92 to provide a high-voltage signal required toclose the N-channel gate during operation. The Dickson charge pump 94 isconfigured to generate an output power signal having a voltage levelthat is greater than a switch assembly source voltage to enable thelevel shifter 92 to operate the N-channel MOSFET switch 90. In oneembodiment, each of the switch assemblies 72 includes an N-channelMOSFET 90, a level shifter 92 coupled to the N-channel MOSFET 90, and aDickson charge pump 94 coupled to the level shifter 92. In anotherembodiment, two of more level shifters 92 may be connected to a singleDickson charge pump 94. Wherever in this specification the term NMOS isused, it could be substituted with a PMOS and vice versa.

In the illustrated embodiment, at least one switch assembly 72 includesa level shifter 92 that is connected to an N-channel MOSFET switch 90.In addition, a Dickson charge pump 94 is connected to the level shifter92 to provide a power signal sufficient to close the gate of theN-channel MOSFET switch 90. In the illustrated embodiment, the Dicksoncharge pump 94 is connected to the source voltage, Vsource, of theN-channel MOSFET and is configured to deliver an output signal to thelevel shifter 92 that has a voltage level that is greater than thevoltage level of the source voltage, Vsource in the case of using anNMOS. In one embodiment, the Dickson charge pump 94 is configured todeliver an output power signal, V_(DCP), having a voltage level that isapproximately 15-20 volts greater than the source voltage, Vsource inorder to assure proper gate operation. The gain controller 82 isconnected to the level shifter 92 for providing a low voltage controlsignal to the level shifter 92. The level shifter 92 is connected to thesource voltage, Vsource, and to the Dickson charge pump 94, and isconfigured to deliver the control signal to the N-channel MOSFET 90having a voltage level sufficient to operate the switch assembly 72 as afunction of the received control signal.

FIG. 13 is a schematic diagram of the secondary power circuit 28including a forward converter circuit 96. In the illustrated embodiment,the forward converter circuit 96 includes a primary voltage reductioncircuit 98 and a secondary voltage reduction circuit 100. The primaryvoltage reduction circuit 98 is configured to receive the intermediateDC power signal from the primary power circuit 26 and deliver asecondary DC power signal to the secondary voltage reduction circuit100. The secondary DC power signal has a voltage level that is less thanthe voltage level of the intermediate DC power signal. The secondaryvoltage reduction circuit 100 is configured to receive the secondary DCpower signal and generate the output DC power signal being delivered tothe electronic device 20.

In the illustrated embodiment, the primary voltage reduction circuit 98includes a transformer 102. The primary side of the transformer 102 isconnected to the primary power circuit 26 and the secondary side of thetransformer 102 is connected to the secondary voltage reduction circuit100. In one embodiment, the primary voltage reduction circuit 98 mayinclude a switch assembly 104 including a FET that is coupled to thetransformer primary side, and a control circuit 103 that is coupled tothe switch assembly 104 for selectively operating the switch assembly104 to adjust a voltage level of the secondary DC power signal. Thetransformer control circuit 103 may include a primary side voltagesensing circuit 105 for sensing voltage and current level of the DCoutput signal and operate the transformer switch assembly 104 tomaintain the voltage level of the DC output signal at a predefinedoutput voltage level and required current level. In this fashion atleast five parts are removed from the equation, which are normallyneeded with a secondary side sense controller, including anopto-coupler, opamp, an inductor, diode and a capacitor. The secondaryvoltage reduction circuit 100 includes a pair of diodes, an inductor,and a capacitor. The forward converter 96 may also include a resistor,capacitor, diode (RCD) circuit 150 (shown in FIG. 37). The RCD circuit150 is configured to perform a transformer reset when the primary sideswitch 104 is off to avoid saturating the transformer 102. The forwardconverter 96 is a pulsed based step down converter. A duty cyclemodulated digital pulse is applied to the primary side switch 104 toconvert the incoming DC voltage to an AC voltage. The transformerwinding ratio provides the step down. In this case, the step down isfrom 11:1. The secondary side sees an ac voltage on its terminals. ThisAC voltage is rectified by the secondary voltage reduction circuit 100diodes and filtered by the LC filter to produce a stepped down DCvoltage on the output. The duty cycle is modulated by either an analogor a digital servo loop. This servo loop looks at the dc voltage on theoutput side, compares it with a response to produce an error signal.This error signal is used to drive a comparator which converts thiserror in a pulse width modulated DC pulse. This DC pulse when applied tothe primary side switch gate 104 corrects the error on the output andmaintains regulation for various load levels.

In one embodiment, the transformer control circuit 103 may include aprimary side current sense circuit 107 that is connected to the primaryside of the transformer 102 to sense the load current and the loadvoltage to facilitate regulating the DC output signal to within 5% of apredefined load voltage. The control circuit 103 uses a current senseresistor 109 and measures across the primary winding. In the illustratedembodiment, the transformer control circuit 103 includes a comparator111 that drives the FET 104. In one embodiment, the resistor 109 is a0.10 ohm resistor. The control circuit 103 is configured to sense theload current on a pulse by pulse basis and sense the peek current. Forexample, in one embodiment, the control circuit 103 senses the voltageacross the resistor 109 and provides the sense current in a voltageformat when the switch 104 is on. When the switch 104 is off, thecontrol circuit 103 senses the differential voltage across the primaryside of the transformer 102 which may be approximately equal to Vprimaryminus the drain of the off transistor 104. When the transistor 104 isoff, there is a drain voltage across it so that is also a sawtoothsignal. Both the voltage and the current are sampled using a switchcapacitor sample and hold circuit that is scaled down to low voltagesand includes resistor dividers to set the differential voltage part ofthe primary winding and bring the voltage into the sample and holdcircuit. The differential voltage is equal to the ΔV across the windingincluding Vprimary and the bottom of the Vprimary. The sample and holdcircuit and the resistor dividers take the primary voltage down to lessthan 5 volts and then takes the deferential that gets the ΔV out. Thesample and hold circuit drives the comparator 111. The other input ofthe comparator 111 is a sample and held peek current voltage that wesense across the 0.1 ohm resistor 109. The inputs into the comparator111 are scaled and gained up and offset so that the inputs are understeady state, and the comparator 111 drives a set-reset flow clock. TheFET 104 includes an AND-gate that is driven by the comparator 111. Aclock off the comparator 111 adjusts the duty cycle of the AND-gate. TheAND-gate also has a high duty cycle driven by a high pulse width clock,which is a sawtooth signal. The other input of the AND-gate is theoutput of the comparator 111 so then the comparator 111 modulates thatduty cycle to small duty cycle or to a large duty cycle. In oneembodiment, the clock is the 100 KHz clock for the forward converterservo loop.

A tertiary winding from the transformer is not needed as a supply forthe sensor. The supply is available from the primary side because thesensing circuit is on the primary side and supply is not needed from thesecondary side. The voltage across the primary side inductor and thecurrent that is going to the primary side FET 104 is used to determinethe output voltage of the system. In one embodiment, the FET 104includes a 200 volt Philips part device having a 2-volt threshold, whichmay use a 5v signal to drive the FET 104 to turn it on without levelshifting. In another embodiment, a 10 volt LDO or 20 volt LDO may beused with a level shifter to go from 5 volts to 10 volts, or 5 volts to20 volts to operate the FET 104.

In the illustrated embodiment, the control circuit 103 uses the senseresistor 109 that is in the drain path of the MOSFET 104 to implement agated approach in which a sample and hold circuit obtains the peekvoltage right when the switch 104 is on between each square wave in thePWM cycle. The gating arrangement samples when the switch is on, becausewhen the switch is off there is no information available at that time.

In the illustrated embodiment, the power circuit 22 is configuredaccommodate different transformers having different turn ratios togenerate a DC output signal having various current and/or voltagerequirements.

In one embodiment, the power circuit 22 may not include the full wavebridge 38, rectifier circuit 30, and input capacitor, 40, such thatV_(LINE) is DC and thus the circuit can receive a direct current (DC) ifthe use case requires, and then conduct the voltage break down asfurther explained herein using the regulated buck circuit 34 and switchcap VB 32 are still used. However, in some use cases, especially withlow DC to DC voltage breakdown, the buck regulator 34 would not beneeded, and only the switch cap VB 32 would be used, whether one stage(as shown in FIGS. 2-12) only would be used. In this case, one couldeliminate the control signal 105 from the output, and rely solely on thecurrent sense resistor 109 and still maintain a tightly regulatedvoltage.

In another embodiment, for DC input variation of the circuit, the usecase may not require a transformer (if the transformer is not needed forthe voltage/current conversion, or if isolation is not needed) like inthe case of an internal part, such as is found in smart phones. In thisinstance, the transformer is not necessary and may be removed from thecircuit together with the FET that drives the transformer. In this casethe entire forward convertor controller circuit 96, 28 can be removed,and the C_(hold) capacitor 36 would be replaced with the sense resistorcircuit segment 109. Further, if an AC circuit does not need to berectified or isolated, than this circuit can work with AC as well as DC.

FIG. 15 is schematic diagram of the power module 12 including a powercontroller integrated circuit (Tronium PSSoC) 106 that may be used withthe electrical power circuit 22. FIGS. 16, 17A, and 17B are blockdiagrams of the Tronium PSSoC 106. In the illustrated embodiment, thepower module 12 includes a printed circuit board 108 and the TroniumPSSoC 106 that is formed within a packaged chip and is coupled to theprinted circuit board 108. At least a portion of the electrical circuit22 is included within the Tronium PSSoC 106. In addition, the digitalcontrol may be conducted by either a microprocessor, external orembedded on the chip or a state machine. In one embodiment, some or allof the electrical circuits and electrical components included in theelectrical circuit 22 are included within the Tronium PSSoC 106. TheTronium PSSoC 106 may be configured for use in two primary power moduleapplications including an Autonomous Power Module (shown in FIGS. 16 and28) and a Universal Power Module (shown in FIGS. 17A, 17B, and 29). Forexample, as shown in FIG. 16, the Autonomous Power Module includes aTronium PSSoC 106 that is configured to operate in an autonomous mode ofoperation that is based upon an analog feedback approach for reducedcost. The Universal Power Module, shown in FIGS. 17A and 17B, includes aTronium PSSoC 106 that is configured to operate in a universal mode ofoperation and that utilizes a microprocessor (0) controller to providefeedback for regulation of the final output voltage.

In the illustrated embodiment, the Tronium PSSoC 106 is configured tomeet predefined requirements for traceability, marking, solderability,and/or solvent resistance. The Tronium PSSoC 106 is marked to indicate adate code, plant identifier, and traceability/authenticity code. Theauthenticity code provides a means of identification and verification asa genuine part against “knock-offs”. All production packaged componentson a tape and reel include the same unique date code, plant identifier,and traceability/authenticity code. Lot segregation may exist in such away as to prevent the mixing of date codes within the same lot ofcomponents. Packaged parts shall be marked to indicate the part number,date code and traceability code. Terminals are configured to meet thesolderability requirements of IPC-J-STD-001 and IPC-J-STD-002 for thepackaged Tronium PSSoC. The packaged Tronium PSSoC and its markings areconfigured to meet the requirements of the MIL-STD-202 test method 215.

The Tronium PSSoC 106 is an advanced power controller integrated circuitdesigned to provide output voltage regulation with high-efficiency andhigh accuracy. The Tronium PSSoC 106 provides the user with amulti-purpose device which can be used in a large variety ofapplications and because of the “Dial-a-Voltage” feature, the same chipcan be configured to work in practically any electronic device.Likewise, programmable output voltages are possible with the TroniumPSSoC, with little or no loss of efficiency across a variety of currentload conditions.

In the illustrated embodiment, the Tronium PSSoC 106 uses the switchcapacitor circuit 32 and the switch-mode buck regulator 34 to maintainhigh-efficiency regardless of the load voltage or current. For example,when no current is being drawn by the load the electronic device 20, theTronium PSSoC 106 enters a low-current mode of operation to minimize thetraditional ‘vampire’ current required to stay awake. In the illustratedembodiment, the Tronium PSSoC 106 includes the single-stage switchcapacitor circuit 32, a PID regulator control block 110 (shown in FIG.20) for PWM control of the forward converter secondary transformer 102,a switch-mode buck regulator controller 112, a buck regulator switchdriver 114, a current and temperature sense blocks 116, 12-bitAnalog-to-Digital Converter (ADC) 118 for voltage and currentmonitoring, a 10-bit Digital-to-Analog Converter (DAC) 120 (shown inFIGS. 17A and 17B) for feedback control, a digital control block 122 forcurrent monitoring state machine, serial input for opto-isolatorcommunications interface, a I2C serial interface port, and power managerunit 124 for on-chip voltage and current generation. Other types ofsensors, such as, sound, photo-detection, radiation and shock can alsobe added depending on the use case.

FIG. 18 is a block diagram of the Power Management Unit 124. In theillustrated embodiment, the power management unit (PMU) circuit block124 generates and supervises the bias voltages and currents required forproper operation of the Tronium PSSoC. Two linear voltage regulatorsprovide regulated 5.0V supplies for the low-voltage circuits of the IC,as well for external support devices such as the opto-isolators and anoptional external microprocessor. In addition to providing properinitialization of the IC upon connection to the line voltage, the PMU124 monitors the voltage supplies for fault conditions and provides amaster power-on-reset (POR) 126. In the illustrated embodiment, the PMU124 includes the bandgap voltage reference, current reference generator,a line-side low-power linear voltage regulator, a transformerprimary-side linear voltage regulator, and power-on-reset. To reducepower dissipation, the line-side circuits are powered from the LINE_0P1pin which supplies a voltage of approximately one-tenth of the LINE_INvoltage (Vline). This voltage is generated internally using an externalresistor divider connected to the LINE_IN and LINE_RDIV pins of the IC.Initialization of the PMU 124 begins with the application of therectified voltage at the LINE_IN pin.

The PMU 124 contains a low-power bandgap reference voltage and currentgenerator for the Tronium PSSoC 106 which is powered from the linevoltage. A high-precision temperature-compensated output voltage isprovided for use as a reference by subsequent circuit blocks, along withmultiple bandgap Proportional To Absolute Temperature (PTAT) currentoutputs. The bandgap output voltage can be trimmed at wafer probe tooptimize the temperature coefficient with the bg_trim[7:0] register bitsand stored in an one-time programmable (OTP) memory stored in amicroprocessor. The bandgap cell is self-starting, requiring only thedefault trim value for initialization. The bandgap cell is not disabledduring sleep mode, but is always powered on, and is designed forultra-low power operation.

The PMU 124 also includes a low-power linear voltage regulator (LPREG)that is provided to convert the high-voltage present at the LINE_INinput of the PSSoC to a regulated voltage for the low-power voltagedomain. The LPREG uses the bandgap reference voltage to generate aregulated output of 5.0V to drive the low power on-chip circuit blocksthat are always powered on including the Low-Frequency Oscillator forthe switch capacitor circuit 32, on-chip logic, etc. An external(off-chip) bypass capacitor may be used for noise filtering, connectedto the LPREG pin. The regulator is not disabled during sleep mode, butis always powered on.

The PMU 124 may also include a primary-side low voltage regulator thatis provided to supply the higher current requirements of off-chipopto-isolators, PWM gate drivers and other support circuits. An external10 μF bypass capacitor is required for noise filtering, connected to theVREG5 pin. The voltage regulator may be disabled for test purposes withthe use of the en_Xv signal. When the en_Xv input to the cell is ‘low’,all of the internal analog currents in the cell are disabled and theoutputs are high impedance.

The POR 126 block monitors the internal supply voltage of the TroniumPSSoC as generated by the LPREG circuit block. For example, FIG. 19illustrates POR threshold voltages that may be used with the POR 126. Inone embodiment, for voltages at the LPREG pin less than the V_(POR)threshold voltage, the POR output will be asserted ‘high’ indicating areset condition. In addition, for voltages at the LPREG pin greater thanthe V_(POR) threshold voltage, the POR output will be de-asserted ‘low’for normal operation. Hysteresis is provided such that a reduction inthe threshold voltage occurs once the V_(POR) threshold is exceeded. Thethreshold derived from hysteresis is then equal to V_(POR)−V_(HYS). Aninverted version of the POR signal may also provided at POR_B.

In the illustrated embodiment, the switch capacitor voltage breakdowncircuit (SCVBC) 32 included in the Tronium PSSoC 106 is configured as avoltage divider through Capacitive Voltage Break Down techniques (CVBD).Through capacitors, it divides the rectified DC voltage present at theLINE_IN pin to a reduced voltage at the CP2_OUT pin for use by theexternal transformer 102 and secondary voltage control loop. Theexternal transformer 102 then further reduces this voltage to thedesired application voltage as a function of the primary-to-secondarywindings ratio. In one embodiment, the SCVBC 32 is configured as acascade of two identical stages, as shown in FIG. 17A. In anotherembodiment the SCVB 32 includes multiple switch capacitor stages, asshown in FIGS. 38-39. The SCVBC 32 is configured to deliver up to 50 mAper Capacitive Break Down block, which consists of Switch Capacitorblocks which provide the voltage breakdown by half or other divisionals.This provides and maintains ≧95% efficiency across the range of loadcurrents from 50 mA to less than 1 mA under light load conditions on theprimary side of the transformer 102. For example, assuming a ≧97%efficiency for the external transformer & rectifier, and overall moduleefficiency of ≧92-97% has been simulated and is achievable. In oneembodiment, the SCVBC 32 may include on-chip fly-back capacitors tomaximize power efficiency, external 2.2 F bucket capacitors and twoexternal 7.5 μF hold capacitors to minimize the voltage ripple. Thesecapacitors are connected to the CP1_OUT and CP2_OUT pins, respectively,for the outputs of the 1st and 2nd stages of the switch capacitorcircuit. Both stages are clocked at a rate of 1 KHz from a two-phasenon-overlapping clock generator which is derived from an on-chip RCOscillator.

Referring to FIGS. 17A and 17B, in one embodiment, for the Tronium PSSoC106, the SCVBC 32 output voltage at CP2_OUT is programmable over therange of 120-90 Volts in steps of 0.117 Volts with the use of an 8-bitbinary-weighted digital-to-analog converter. The SCVBC output is limitedto this range to ensure that the forward converter transformer 102provides most of the output current in the step-down process. The SCVBCis limited to an output current of 50 mA. If additional current isrequired for the application, the switch-mode buck regulator 34 may beenabled to provide up to 430 mA of current. Each stage of the SCVBC 32may be programmed to produce a voltage conversion ratio. Thisprogramming is done automatically in the Course Gain Control where therectified LINE_IN voltage is compared to the 8-bit DAC setting. Thedigital control of this DAC enables multiple voltages to be programmedto obtain the desired final output voltage required for the targetapplication. An example of the load voltages which can be programmedwith the DAC as a function of the transformer turns ratio.

Referring to FIG. 16, in one embodiment, the SCVBC 32 may include asingle-stage switch capacitor circuit with a corresponding divider ratioof 1, 0.66 or 0.5. The output voltage present is then reduced by theexternal (off-chip) forward converter 96 to obtain the final applicationoutput voltage of 5.0V. All analog and digital signals for the SCVBC(and Buck Controller) are generated in the 5V domain. The SCVBC ErrorVoltage is scaled to be within the XV domain using a resistor divider.The LINE_IN voltage is also scaled so that processing can be done withinthe XV voltage domain.

In one embodiment, shown in FIG. 16, the SCVBC 32 includes a GainControl block that uses the scaled LINE_IN voltage to determine theappropriate divider ratio for the SCVBC 32. The scaled LINE_IN voltageis compared to the Bandgap reference voltage to select one of three ormore possible divider ratios as a function of the AC Mains voltage.Final regulation of the output voltage may performed in the switchcapacitor regulator where the clock is turned on and off to control theamount of charge delivered to the hold capacitor.

Referring to FIGS. 17A and 17B, in one embodiment, the SCVBC GainControl block may use the scaled LINE_IN voltage and Output Voltage DACsetting to determine the appropriate Course Divider ratio derived fromthe combined divider steps in CP1 and CP2. In this way, settings for the120 and 90 Volt outputs as a function of world-wide AC input voltagescan be achieved. Final regulation of the CP2 output voltage is performedin the switch capacitor regulator where the clock is turned on and offto control the amount of charge delivered to the CP1 and CP2 holdcapacitors. The lowest divider ratio required for CP1 and CP2 should beprogrammed for the CP1 stage to minimize the voltage drop across thehigh-voltage NMOS switches.

The CP2 output feeds the primary winding of the Forward Regulator. Thefinal output voltage of the system is set by the following equation:

(V _(SET) /XFMR _(RATIO))*dC=V _(OUT)

Where dc is the duty cycle for the Forward Regulator and should bemaintained at 0.5 or less to ensure the system transformer does notsaturate.

The SCVBC 32 includes a Dickson charge pump (DCP) 94 (shown in FIGS. 5and 6) that may be used to provide a boosted voltage for the gates ofthe NMOS high-voltage switches. The DCP's may be clocked at a clock rateof 1.6 MHz and generate gate voltages equal to the voltage at theLINE_IN pin plus approximately 18V. In addition, each NMOS high-voltageswitch 90 may include a corresponding level shifter to translate thedrive signal from the low-voltage domain to the boosted voltage providedby the DCP's. In one embodiment, this requires dual level shifters,other requirements may only need one level shifter. The input to thelevel-shifter is 5V and is translated to the 20V domain for use by theSCVBC 32. This same type of level shifter, scaled for output currentdrive, may be used throughout the Tronium PSSoC 106.

In one embodiment, as shown in FIGS. 17A and 17B, the Tronium PSSoC 106may include a Digital-to-Analog converter (DAC) that providesprogrammability for the output voltage of the switch capacitor circuit.An R2R current-mode DAC topology digitally scales the bandgap referencevoltage to the control voltage required by the switch capacitor circuitto maintain the output voltage programmed by the user. The outputvoltage range of the DAC is from 120-90V programmed in steps of 118 mVby the CP_DAC[7:0] register bits.

The SCVBC 32 may also include a switch capacitor regulator that includesa comparator and an AND gate that are used to control the charging ofthe SCVBC. In one embodiment, the comparator's inputs may include theOutput Voltage DAC and the scaled version of the CP2 output voltage. Forexample, if the scaled voltage from the CP2 output is greater than theDAC voltage, the comparator output is low and the 1 KHz CP clock isgated OFF. If the DAC Voltage is greater than the scaled CP2 outputvoltage, then the comparator output is asserted high and the AND gateenables the clock to charge up the output. In addition, the comparatormay be designed with hysteresis to minimize the CP2 output voltageripple. Moreover, the regulator may run both CP stages in thediscontinuous mode; that is, the clock pulses are only present whencharging of the 7.50 hold capacitors is required.

In the illustrated embodiment, if a stack of CVBD Modules are not used,then large current loads (up to 430 mA or more) are easily handled withthe use of a hybrid topology which includes a Switch-Mode Buck Regulator(SWR) 34 and the CVBD Module. The Tronium PS SoC 106 contains thecontroller for the SWR 34, which makes use of an external (off chip)PMOS switch (which can be an internal to the Chip PMOS or NMOS [withadditional Dickson Charge Pumps for gates]) to supply the high-currentdemands of the load. Since the high-current path is external to thePSSoC, the PSSoC is not required to dissipate the majority of the loadcurrent. This improves the overall system efficiency by eliminating thesource of additional parasitic losses in the PS SoC due to theON-resistance of the high-voltage devices. The SWR may be regulated atthe same frequency as the CVBD Module, or run at higher (500 KHz-1 MHz)to very high frequencies, while the CVBD Module is running at lowerfrequencies in order to remain more efficient. (The CVBD Module can berun at higher frequencies, but with current devices offered insemiconductor platforms today, this increases gate openings/closings,which increases losses).

In one embodiment, the buck regulator 34 may include the followingexternal (off chip) components: 1. Series High PMOS Switch. The PMOSSwitch may be selected for low RDS_(ON), low input capacitance and aV_(DS) of >400V; 2. High Voltage Buck Diode with High Volt Breakdown,extremely low leakage and switching current; and 3. Buck Energy StorageInductor. The inductor must have low ESR and be able to handleappropriate de-rated current. However, these parts, usually depending onthe frequency which runs the Buck (the higher the frequency the smallerthe value of the parts needed), may be internal devices/components onthe chip, and not external. With the application of GaN and/or GaA andDeep Trench Capacitor technologies, as well as technologies which puttransformers on the chip, all parts may exist on one chip.

The Tronium PSSoC 106 may also include a high-frequency oscillator thatis divided down to produce a 100 KHz (nominal) clock for use by the BuckRegulator PWM controller. The 100 KHz clock is dithered with a pseudorandom algorithm in the Digital Control block to ensure the suppressionof harmonics in the EMI spectrum. This clock is then Pulse WidthModulated to control the on/off time of the external Buck RegulatorPMOS/NMOS FET. The 100 kHz clock is converted to a saw-tooth ramp insidethe Tronium PSSoC 106 where it is compared to the Error Amplifieroutput. The Pulse Width Modulated signal from the Comparator output isthen applied to the level shifter input to control the on/off time ofthe external Buck Regulator PMOSFET. The Error Amplifier of the Buckregulator 34 receives feedback from the regulator by scaling the voltageat CP2_OUT with the use of a resistor divider. The voltage feedbacksignal is then conditioned using internal resistors and capacitors tocontrol the response of the Buck Regulator under all conditions. Theresulting transfer function for the regulation servo loop is comprisedof multiple poles and zeros to ensure that the regulator output isstable for the full range of load conditions from 50 mA to 430 mA. TheError Amplifier and PWM Controller for the Buck Regulator are alllocated in the 5 Volt domain with the final control signal being levelshifted to drive the external high-voltage PMOSFET switch.

The Tronium PSSoC 106 may also include a LDO Buck Regulator 128 that isused to create the high-side voltage necessary to drive the gate of thePMOS/NMOS FET for the Buck regulator 34. This voltage is then used tosupply the gate voltage required to drive the external PMOS/NMOS FET. Acapacitor is connected for filtering.

In the illustrated embodiment, the Tronium PSSoC 106 includes a CurrentSense Amplifier of the Tronium PS SoC senses the voltage across theexternal current sense resistor at pins RCSP and RCSN. This voltage issampled and held by a switched-capacitor difference amplifier anddigitized by the on-chip general-purpose ADC. The digital word is thencompared against programmed thresholds to enable or disable the BuckRegulator 34 as needed to optimize efficiency. The output of the CurrentSense Amplifier is also monitored for possible fault or alarm conditionssuch as over current, allowing a digital state machine that controls thecurrent sense feedback to disable the SCVBC 32 to prevent possibledamage.

The Tronium PSSoC 106 may also contain at least two free-running RCoscillators which share a common trim controller including a 16 KHz RCOscillator and a 9.6 MHz RC Oscillator. The oscillator frequencies canbe trimmed using the osc_trim register bits.

The low-frequency (16 KHz) RC Oscillator is a line-side RC Oscillatorthat runs continuously after the application of the line voltage atLINE_IN. It is supplied by the LPREG regulator. This oscillator outputfrequency is divided down to a number, like 1 KHz to provide the clockfor the SCVBC 32. The oscillator output, in that case, is also used asthe reference clock for the Sleep mode Shut-down Timer. A high-frequency(9.6 MHz) RC Oscillator provides the master clock for the decoding ofthe single-wire serial data input. The oscillator 9.6 MHz output isdivided by 6 to provide the 1.6 MHz clock required by the Dickson ChargePumps in the switch capacitor circuit. It is further divided to providethe clock source for the Buck Regulator and Forward Converter PWMControl Blocks. These 100 KHz clocks are dithered with a pseudo randomalgorithm by the digital logic to ensure suppression of the harmonics inthe EMI spectrum. The oscillator can be enabled with the osc_en registerbit and is powered by the LPREG regulator on the line side.

In the illustrated embodiment, the Tronium PSSoC 106 includes anultra-low power ADC 118 to digitize a temperature sensor and currentsense amplifier analog voltages. These digitized voltages can then becompared by the Digital Control block to disable or restart the analogcircuitry. The ADC uses a successive-approximation (SAR) topology forlow-power and enhanced INL/DNL performance. The input to the ADC isprovided by a multiplexer. The multiplexer can select each of thechannels of interest for digitization by the ADC. The converted samplevalues are then stored in the ADC_SAMP register for use by the ControlState Machine. The ADC uses a low voltage supply and will be disabledwhen the device is in sleep mode.

FIG. 20 is a schematic illustration of a Proportional to Integral andDifferential (PID) Regulator Control circuit 110 that may be used withthe Tronium PSSoC 106. In the illustrated embodiment, the Tronium PSSoC106 includes a PID servo loop 130 to regulate the voltage at the outputof the forward converter 96 as load current is drawn from thesecondary-side of the external transformer. The PID block includes anError Amplifier, Saw-tooth Waveform Generator, Comparator and PWM ClockControl Block. The PID loop is designed to regulate the output voltageunder heavy fluctuation of load current without triggering anyinstability.

A PID Buffer Amplifier receives the feedback to close the Forwardregulation loop via the AUTO_ERR input. This is the output of theOpto-Isolator which provides a voltage to the PSSoC which represents theoutput voltage of the Forward Converter. This voltage is then scaled onthe PSSoC with a resistor divider and buffered for the Error Amplifier.

The Error Amplifier for the Autonomous PID Loop is located on theTronium PSSoC with the compensation resistors and capacitors on-chip.The Error Amplifier uses the bandgap voltage as the reference for thePID Servo Loop. A Saw-tooth, or other, Waveform Generator provides aclock-based means of pulse-width-modulation (PWM) for the PID ServoLoop. The circuit receives the 100 KHz clock from the digital logic andconverts it to a saw-tooth waveform of the same frequency to be comparedto the output of the Error Amplifier. The outputs of the Error Amplifierand Saw-tooth Waveform Generator are compared by the PID Comparator togenerate the PWM clock required to drive the Forward Converter. A DutyCycle Limiter is provided to ensure that the PWM output provided by thePID Comparator does not exceed 65%. This output is applied at the FWDOUTpin to drive the external transformer. In normal operation, the PWM dutycycle is limited to a range of 10-65% to avoid saturation of thetransformer.

In one embodiment, the PID Servo Loop is designed to operate at lowvoltage and deliver a maximum of the required DC current to the load.The regulation can be controlled up to a high percentage of absoluteaccuracy by using an LC filter on the secondary side and by properlysizing the internal R's and C's of the 3^(rd) order compensationnetwork. The LC filter double pole is given by the following equation:FLC=½π√L1C4.

The C1 capacitor has a certain ESR (series resistor) which produces azero. This zero generates a +90 degree phase shift: FESR=½πC1RESR.

The compensation loop has a certain bandwidth (Fc) which isapproximately 1/10th of the clock rate of the forward converter. Thegoal of the network is to maintain at least 45 degrees of phase marginat Fc: Phase Margin=180 degrees+Phase of loop.

The PID loop has 2 zeroes and 2 poles. The 2 zeroes are necessary toprovide 180 degree of phase boost in order to negate the 180 degree ofphase loss due to the output LC filter. Both zeroes are placed at about˜50% of the LC filter pole frequency. Two poles are then located at theswitching frequency of the converter (100 KHz). This allows us tocalculate C1, C2, C3, R2 and R3. R1 is set to a reasonable value inorder to start the calculation procedure.

In another embodiment, the PID Servo Loop is designed to operate formultiple output voltages which can be programmed by the user for therequired application. The loop may deliver ny current, but in thisillustrated case 4.5 A of DC current to the load with a regulation of upto 0.1% of absolute accuracy. Feedback for the Universal loop isprovided by the external microprocessor and voltage sense supportcircuits, and is input to the Tronium pin as a serial data stream. Aparallel-to-serial conversion is then performed on the digital wordwhich is converted to an analog voltage for application to the erroramplifier as shown in FIG. 20. Conversion to analog is performed with anon-chip DAC which is updated at the frequency of the incoming data rate.The reference voltage for the PID error amplifier is generated by asecond DAC which is programmed by the microprocessor.

A Digital-to-Analog converter (DAC) generates the analog referencevoltage for the PID Control Loop based upon the digital programmed inputfrom the microprocessor. The Digital-to-Analog converter (DAC) as shownis a 10-bit scheme, but can be any number of bits. The DAC may alsoprovide feedback for the PID Control Loop by converting the digital wordreceived from the pin to an analog voltage for input to the loop. TheDAC voltage is input to the error amplifier and compared to the analogreference voltage to produce the error voltage for the control loop. TheDAC provides updates to the loop at the rate of the incoming data.

Referring to FIGS. 17A and 17B, in one embodiment, the Tronium PSSoC 106may include an on-chip ΔV based temperature sensor that enables the ICto sense the temperature of the die or module. In this example, ageneral purpose 12-bit ADC is used to digitize the differential voltage.The digitized value is then compared to programmable thresholds in orderto shut down or re-enable the Tronium PSSoC depending on temperatureconcerns.

In the illustrated embodiment, the Tronium PSSoC 106 provides two modesof operation and four wake-up states (W0-W3) applied upon powerup.

Startup Mode. During Startup Mode, the Tronium PSSoC controls thestartup behavior of the module when power is first applied or when aphone is plugged in (in the case of a charger). When power is firstconnected to the AC Mains, the rectified and filtered LINE voltagepresent at the LINE_IN pin of the IC increases until it reaches itsfinal DC value. The basic support circuits of the Tronium PSSoC areconsequently powered up to initiate the power management functions. Atiming diagram of an exemplary startup sequence of events is shown inFIG. 24, beginning with the application of the LINE_IN voltage at t=0.

The line side has three circuit blocks that are always powered ON: 1.Low-Power Bandgap Reference; 2. Low-Power 5V Regulator (LPREG); and 3.Low-Frequency RC Oscillator. Other circuits may be powered, but in thisexample it has been reduced to three in this instance in order to drawextremely low stand-by power. These circuits draw power directly fromthe LINE_IN input with no transformer action to increase the availablecurrent. As a result, they are designed for ultra-low power consumption.Alternatively, the transformer could be enabled, but this would reduceefficiency.

Normal Mode. Following the application of power and the completion ofthe wake-up states, the Tronium PSSoC 106 will enter the Normal Mode ofoperation. The Normal Mode of operation is maintained until thevoltage/current becomes extinct or passes a low current threshold wheretypically the microchip inside the battery system begins resisting thecurrent to prevent overload. In the normal mode of operation, theTronium PSSoC exits the Sleep Mode as a result of the detection of loadcurrent. Regulation of the load occurs as the Buck Regulator and SCVBCsupply the necessary current. In this mode of operation all Troniumcircuits are powered ON and responding to the external stimulus.

In one embodiment, combining the elements of Normal Mode, Start Up Modeand Sleep Mode the battery can be provided a “bump” charge. In thisinstance another mode, called Bump Charge Mode would be executed when itis determined by the logic in the chip that a full charge has beenexecuted, meaning a drain from a higher current to lower current over agiven period of time. This Bump Charge mode of operation can exist inthe state machine or be enabled/disabled via the I2C interface and wouldinstruct the circuit to “disconnect” several times and begin rechargingup to a maximum threshold of approximately 150 milliamps with aninterval in between. In this fashion, the battery would be prompted toreceive an additional trickle charge to ensure that it is really full,not just stating “full” on the device battery indicator. This will solvethe problem where cell phones only charge to about 80-90% of theirbatteries capacities, thus, over time, while the indicator stillregisters the battery at 100%, it is really a 100% of 80% of thebattery's capacity, not 100% of 100% of the battery's capacity. Underthe Bump Charge Mode, the Tronium PSSoC digital provides an additionalcurrent threshold which is higher than the sleep threshold so that theSleep Mode function, set out below, is not compromised.

Sleep Mode. The Tronium PSSoC must use minimal power when connected tothe AC Mains power and no charging or power supply function is required.This requires the electrical circuit 22 to have at least two distinctpower domains: 1) the line side domain and 2) the primary side domain.The line input side is the domain that must be capable of being poweredat all times. There is also a 1.6 MHz RC oscillator that is used for theDickson Charge pumps. This oscillator remains OFF in the SLEEP mode. The16 KHz oscillator is used as a countdown timer to wake the Tronium PSSoCwhen the programmed countdown time has been reached.

In the illustrated embodiment, the Tronium PSSoC 106 includes a DigitalControl block 122 that provides the user the ability to manage numerousaspects of the Tronium application in setup, programmable, normal, test,or evaluation modes of operation. A microprocessor or state machines areprovided to monitor the output voltage and current of the Switchcapacitor circuit and include configurable registers which providefeature selection and programmability for both the normal mode ofoperation and the low-current or ‘sleep’ operating mode. Communicationinterfaces are also provided for external devices as required by theapplication.

FIG. 21 is a block diagram of a Tronium universal digital control block132 that may be used with the Tronium PSSoC 106. FIG. 22 is a blockdiagram of a Tronium autonomous digital control block 134 that may beused with the Tronium PSSoC 106. FIG. 23 is a flow chart illustrating amethod of operating the power circuit 22. FIG. 24 is a graphicillustration of a state transitions that may be implemented by theTronium PSSoC 106.

Referring to FIG. 21, in one embodiment, the Tronium PSSoC 106 includesthe universal digital control block 132. The Tronium universal digitalcontrol block 132 provides the following functions for control of theUniversal Module: Control State Machine, Clock Generator, ADCController, Clock Dither LSFR, I2C Interface—Mono or Dual CommunicationMode, Programmable Communication Mode, microprocessor Interface,Test/Eval Multiplexer, and/or Register File.

The Control State Machine or microprocessor/microcontroller determinesthe proper operating mode of the Tronium Module by monitoring the outputcurrent of the switch capacitor circuit. At least two modes of operationare provided including a Sleep mode and a Normal regulation mode. TheControl State Machine or microprocessor also provides four states towake-up the PSSoC, plus the Bump Charge Mode, upon the first applicationof power, or when exiting from the Sleep mode. In addition, the statemachine or microprocessor continually monitors the output voltagecurrent for an over-or-under-current alarm condition.

Monitoring of the switch capacitor output current is achieved in theanalog subsystem or in the microprocessor with the use of a CurrentSense Amplifier and an Analog-to-Digital Converter (ADC). The DigitalControl block provides control of the ADC and can perform periodic gainand offset correction for the ADC. The ADC samples are then compared tothe programmed digital thresholds for switch capacitor current requiredby the Control State Machine.

A Clock Generator provides the clocks required for the analog anddigital subsystems, and also enables clock gating to minimize powerconsumption in the Sleep mode of operation.

The Digital Control block provides a single-wire serial interface tosupport configurability of the PSSoC via an external microprocessor; ora multi-wire interface which will support two way communication betweenthe Tronium PSSoC and the microprocessor or state machine. A ClockDither Linear Feedback Shift Register (LSFR) is included to generatepseudo-random numbers for dithering of the Forward and Buck RegulatorPWM clocks. The pseudo-random number is used by the analog subsystem todither the high-frequency oscillator output. An I2C port is included formanufacturing settings, test, evaluation, updates, health-checks anddebug. The Register File which contains configuration registers fordevice operation can be accessed using the I2C interface. A digitalmultiplexer is provided to selectively multiplex various internaldigital signals to the DIGTST output pin for test purposes.

Referring to FIG. 22, in one embodiment, the Tronium PSSoC includes theautonomous digital control block 134 that provides the followingfunctions for control of the Autonomous Module: the Control StateMachine or microcontroller; Clock Generator; ADC Controller; ClockDither LSFR; I2C Interface; Test Multiplexer; and Register File. TheControl State Machine determines the proper operating mode of theTronium PSSoC 106 by monitoring the output current of the switchcapacitor circuit at the CP_OUT pin. Two modes of operation are providedincluding a Sleep mode and a Normal regulation mode. The Control StateMachine or microcontroller also provides four states to wake-up the ICupon the first application of power, or when exiting from the Sleepmode. In addition, the state machine monitors the output current for anover-under-current alarm condition and Bump Charge Mode.

Monitoring of the switch capacitor output current is achieved in theanalog subsystem with the use of a Current Sense Amplifier and an 12-bitAnalog-to-Digital Converter (ADC) is used in this example. The DigitalControl block provides control of the ADC and can perform periodic gainand offset correction for the ADC. The ADC samples are then compared tothe programmed digital thresholds for switch capacitor current requiredby the Control State Machine and/or microcontroller.

A Clock Generator provides the clocks required for the analog anddigital subsystems, and also enables clock gating to minimize powerconsumption in the Sleep mode of operation or Bump Charge Mode.

A Clock Dither Linear Feedback Shift Register (LSFR) is included togenerate pseudo-random numbers for dithering of the Forward and BuckRegulator PWM clocks. The pseudo-random number is used by the analogsubsystem to dither the high-frequency oscillator output.

An I2C port is included for manufacturing settings, evaluation,upgrades, resets, chip health-checks, test and debug. The Register Filewhich contains configuration registers for device operation can beaccessed using the I2C interface.

A digital multiplexer is provided to selectively multiplex variousinternal digital signals to the DIGTST output pin for test purposes.

In the illustrated embodiment, the Tronium autonomous digital controlblock 134 includes a State Machine to determine the proper mode ofoperation for the Autonomous Module based upon the load current.

As shown in FIGS. 23 and 24, the Control State Machine provides fourwake-up states (W0, W1, W2 and W3) and two operating modes; a NormalMode and a Sleep Mode.

Wake-Up 0 (W0)—When power is applied, the line-side circuits wake up:the bandgap (BG) and the low-power regulator (LPREG) power up. After theLPREG is stable, por_b is released and the system transitions to Wake-Up1 (W1).

Wake-Up 1 (W1)—The low-frequency oscillator (LF_OSC) and thegain_control (GAIN_CTRL) get enabled. At the same time, thehigh-frequency oscillator (HF_OSC) and the charge_pump (CP) get enabled.The CP is set to not regulate. When the LF_OSC is stable, the lf_clk tothe digital block is released at which point (a) the 10 mS counterstarts up and (b) the 1 kHz clock to the switch capacitor becomesactive. When the 10 ms counter expires, the system transitions toWake-Up 2 (W2).

Wake-Up 2 (W2)—The switch-regulator (SWR) gets enabled, the CP is set toregulate and the 1 mS counter starts. When the 1 mS counter expires, thesystem transitions to Wake-Up 3 (W3).

Wake-Up 3 (W3)—The forward PID gets enabled and two counters start up:the 20 mS counter and the 250 mS counter. The following scenariosprovoke transitions from this state: a. The 20 mS counter expires andthe forward PID override option is on: The system transitions to normalmode (NM); b. The 20 mS counter expires, the forward PID override optionis off and the forward PID stabilizes before the 250 mS counter expires:The system transitions to normal mode (NM); c. Sleep mode is notdisabled, the forward PID override option is off and when the 250 mScounter expires, the forward PID has not stabilized yet: The systemtransitions to sleep mode.

Normal Mode (NM)—The current sense block (CUR_SNS) and the ADC getenabled. If self-calibration is not disabled, the ADC uses the first twosamples for gain and offset calibration and signals that the ADC data isokay when the third sample is ready. If self-calibration is disabled,the ADC performs gain and offset correction with the values programmedin the designated registers and signals that the ADC data is okay whenthe third sample is ready. When the ADC data is okay, the systemmonitors the current load. The following mutually exclusive conditions,the thresholds for which are programmable, can occur: 1. Over-currentcondition: The system sets the over-current status bit. If sleep mode isnot disabled, the system transitions to sleep mode (SM); and 2.Under-load condition: If the LCSD_EN pin is high and sleep mode is notdisabled, the system transitions to sleep mode (SM); and 3. Low-loadcondition: The system shuts down the SWR when it detects a low-loadcondition and turns the SWR back when the low-load conditions subsides.

Sleep Mode (SM)—The system disables the HF_OSC, the CP, the SWR, theforward PID, the CUR_SNS) and the ADC. It also starts the sleep counter,the duration of which is programmable. The default sleep time isapproximately 5 seconds, which may be adjusted depending on useapplication. The system stays in sleep mode if the forward PIDpreviously hadn't stabilized on entry to sleep mode. In this case, thesystem can be restarted in W1 by triggering the EXT_RST pin or in W0 byremoving power. If the forward PID was okay on entry to sleep mode, thesystem transitions to the W1 state when the sleep counter expires.

In the illustrated embodiment, the transition between the Normal andSleep modes of operation is achieved by monitoring the output current ofthe switch capacitor circuit via the Current Sense Amplifier and theADC. In addition, the Control State Machine can disable the SWR BuckRegulator if the load current decreases to the programmed digitalthreshold. Monitoring of the current and the corresponding modetransitions is illustrated in the diagram of FIG. 24.

Referring to FIGS. 21 and 22, the digital control block 122 may includea clock generator which generates all the clocks required by the digitalsubsystem. Three clock domains are provided which are asynchronous toeach other, a low-frequency clock domain, a high-frequency clock domain,and a I2C clock domain.

The Low-Frequency Oscillator in the analog subsystem provides a clock,in the illustrated example, a 16 kHz clock for the digital subsystem(lf_clk). In addition to the clock used by the Register File, the ClockGenerator derives the following clocks from lf_clk: 1. sys_clk—An 8 kHzclock with a 50% duty cycle which clocks the control state machine. 2.adc_gclk—A gated version of sys_clk which clocks the ADC controller.This clock is gated off in sleep mode. 3. lfdiv_clk—A divided clock witha programmable frequency of 1, 2 or 4 kHz with a 50% duty cycle to beused in the analog block. This clock is gated off in sleep mode.

The oscillator can be bypassed in the analog subsystem via the TSTMD0input to enable the application of a 16 kHz clock from the EXT_CLK pin.

The High-Frequency Oscillator in the analog subsystem provides a 1.6MHz, 50% duty-cycle clock which is further divided by the ClockGenerator to create the hfdiv_clk. The hfdiv_clk is programmable via theRegister File to provide frequencies of 100, 200, and 400 kHz. Thehfdiv_clk is also used in the digital for the Clock Dither LFSR and inthe analog for the Buck Regulator and Forward PID loops. The clock shutsoff in sleep mode when the HF Oscillator is disabled in the analog.

The I2C Interface uses the clock input at the SCLK pin to controloperation of the I2C port. Data rates of up to 100 Kbps are supported.

In the illustrated embodiment, the digital control block 122 alsoincludes an ADC controller which generates the control signals for thegeneral purpose 12-bit ADC in the analog subsystem. It also controlsselection of the input to the ADC for conversion via the ADC multiplexerand the ADC_MUX_SEL registers in the CONTROL0 register. The ADC outputformat is magnitude. The Digital Control block performs aself-calibration routine once when the ADC is first enabled. The DigitalControl block can configurably use the gain and offset correction valuescalculated during the self-calibration, or use the gain and offsetcorrection values written to the ADC_GAIN and ADC_OFFS registers.

During the self-calibration routine the offset and gain correctionvalues are determined as described below.

The Offset is determined first as follows: Set the ADC input mux toselect the Reflo reference voltage. Do one ADC conversion. The Idealvalue would be 0. Load the ADC Conversion data into the local ADC OffsetCorrection Register.

The Gain is determined next as follows: Set the ADC input mux to selectthe Refhi reference voltage. Do one ADC conversion. The Ideal valuewould be 4095. Load the local ADC Gain Correction register with theresults of (ADC Conversion data−Offset Correction)/4095.

Following the self-calibration phase, the ADC Conversion values arecorrected as follows: ADC Corrected data=(ADC Conversion data−OffsetCorrection)/4095.

The Clock Dither LFSR provides pseudo-random number values to implementdithering on the 1.6 MHz clock to mitigate EMI. The LFSR is a 12-bit,maximum-sequence, Galois-type LFSR with the polynomial of x12+x6+x4+x+1.The dither value is generated as shown in the table below. The ClockDither LFSR can be selectively enabled or disabled with the dith_enregister bit in the Control register.

In one embodiment, the Tronium PSSoC digital control block 122 mayinclude a configurable down counter with a range of 0.512 Sec to 16.384Sec, to implement the Sleep Timer function. The Step size is 512 mS. Thecounter receives its clock from the Clock Generator block where it isdivided down from the LF Oscillator clock. The counter is loaded withthe sleep_time value programmed in the SLEEP_CTRL register. The counterwill count down from this value until it reaches zero at which time itnotifies the Control State Machine that the Sleep Timer has expired.

FIG. 25 is a schematic illustration of a communication interface thatmay be used with the Tronium PSSoC 106. FIG. 26 is a schematicillustration of a microprocessor communication protocol that may be usedwith the Tronium PSSoC 106. In the illustrated embodiment, thecommunication may be uni-directional or bi-directional. The TroniumPSSoC 106 contains one or more communication interfaces, here describedas three interfaces: 1) a microprocessor interface, 2) a single or dualcommunications/update interface for programming values or returninginformation to the state machine/micro, and 3) a test/eval interface.The microprocessor interface will be used to communicate with anexternal microprocessor for certain products, the communications/updateinterface may update the micro or any of the values internal in thechip. This allows for product configurability and for implementation ofa control loop for the Tronium charger. For the Tronium PSSoC, this canbe either a read/write or a write only interface, i.e. themicroprocessor will or will not be able to read from the PSSoC dependingon the type of communication determined: one way or multilateral.

The test/eval interface will be used in the manufacturing testenvironment, and for bench evaluation of the Tronium PSSoC. It willallow for write and read access to the on-chip registers. The upgrade,eval, health-check and reset interface will be used to reprogram a chip,change its voltage/current output, or change other reprogrammableportions of the control logic, including thresholds, as well as runscans to help determine if anything is wrong with the chip(health-check).

Typically, only one interface can be selected at a time, but this can bechanged based on the state machine or micro settings. The IF_SEL inputpin selects the I2C when ‘1’ and the microprocessor interface when ‘0’.

Microprocessor Communication Interface. The Tronium PSSoC may alsoprovide a single-wire serial interface to support configurability of thePSSoC. The interface consists of uni- or multi-directional datainput/output. The protocol is shown in FIG. 26. All packets will behomogenous in structure and length unless otherwise necessary. Eachpacket will be a certain number of bits. The packet fields are describedbelow. By adding another wire, a dual communication interface may be hadso that the information is multi-directional.

To support reliable communication, the data may be Manchester Encodedper the IEEE 802.3 Communication Standard. The receiver will then use anover-sampling clock to maintain bit synchronization over the packet. Thebit rate will be 600 Kbps. The incoming data will be oversampled by afactor of 16 times the bit rate. The oversampling clock is therefore 9.6MHz, and is sourced from an on-chip RC oscillator.

Start: A single bit whose value is the non-idle state of the signalline. This will be ‘1’ for this application. R/W: A single bit toindicate a read or write request. When ‘0’, the data is written to theselected Tronium register. Note that Tronium only supports writeaccesses. Addr[4:0]: 5 bits used to address the Tronium configurationregisters. Data[9:0]: 10 bits to be written to the selected Troniumregister. For cases where the target register is less than 10 bits, datawill be right justified. For example when writing to an eight bitregister, Data[7:0] will be written to the addressed register location.Idle: A single bit whose value is the idle state of the signal line.This will be ‘0’ for this application.

Data is transferred MSB first. For example, Addr[4] is transmitted firstin time by the host. The Tronium implementation will or will not supportread operations of the ASIC registers by the host depending on theprogramming. The R/W bit is included for future expansion.

FIG. 27 is a schematic illustration of an Inter-Integrated Circuit 136that may be included in the Tronium PSSoC 106. In the illustratedembodiment, the Tronium PSSoC 106 contains an I2C slave port to supporttesting of the device. The I2C address is configurable using theI2C_ADDR pins. The I2C_ADDR inputs are compared to the I2C Slave Addressbits. The Tronium I2C Bus protocol is shown FIG. 27. The I2C Interfacesupports bit transfer rates up to 100 Kbs. The I2C interface runsentirely off the I2C SCLK clock input.

I2C Write Operations: The Tronium PSSoC supports writes to the TroniumMemory Mapped registers over the I2C Slave port. After receiving an I2Cslave address which matches the Tronium I2C address, the next byte,shown as byte1 in FIG. 27, will contain the 5 bit address field for theTronium Register File addresses. The Tronium PSSoC only supports accessof one register per command.

I2C Read Operations: The Tronium PSSoC supports reads from the TroniumMemory Mapped registers over the I2C Slave port. The read operationrequires two I2C operations. First, an I2C write to the RDREQ registerwhere the data in byte2 is the Tronium Memory Map address of theregister to read. Then an I2C read command will read the requestedregister. The Tronium only supports accessing one register per command.

Note that there is a delay between the I2C Write operation and the timeat which the RDREQ register is updated. This means that following theI2C Write operation, the I2C Master must wait 400 μsec before issuingthe I2C Read operation. This wait time only applies to the first I2Cread following the I2C Write to update the RDREQ register.

In one embodiment of the Tronium PSSoC the digital memory hasintelligence where if the Tronium PSSoC is powering a television, if atelevision has not been used from a certain time period to another, suchas midnight to 7:00 o'clock A.M. for a fixed number of days, the Troniumwould always put itself into Sleep Mode during these times to conserveenergy and not re-engage in the current sensing routine of the wake-upsequencing.

In another embodiment of the invention, the Tronium PS SoC is connectedthrough its I2C interface to wireless (like BlueTooth®) or power-linetype communication protocols and devices, either external, on-chip oron-module, in order to receive instructions to the state machine ormicroprocessor. In this fashion there could be “real-time” instructionsgiven to the Tronium about when to go to Sleep Mode, when to wake up,and reset, upgrade or change other preconditions, like over-voltage orPWM regulation. In this fashion, the Tronium PSSoC can have “real-time”sensing and switching of its control mechanism to achieve differentlevels of frequency, speed, or adapt to low power situations, like insome countries, where the grid typically runs under-voltage duringsignificant portions of the time. In this case the Tronium PSSoC can getreal-time information about resets, operation, or shutdowns/restarts,including real-time commands from its owner, even from a cell phone ortablet through the use of cell system to inside the home communicationtechnologies. In this case a person may want to shut down power tocertain electronic equipment or electronic devices powered by theTronium PS SoC while away, and this could be accomplished through thecommunication interface over wireless or wire communication technologiesgiving specific instructions through the I2C interface in the TroniumPSSoC, instructing it to shut down the device, and even pre-setting thetime it should wake up.

In another embodiment of the invention, and when used as a charger orconstant supply power, the Tronium PSSoC is small enough to fit into awall plug attached to the cord, therefore eliminating the need for acharger “box” or laptop “brick”.

In one embodiment, the Tronium PSSoC 106 has several test structures tosupport manufacturing, programming, eval, upgrading, health-check,communication, test and bench evaluation. The Tronium PSSoC provides twotest registers for controllability and observability of key internalfunctions and control signals. The TEST_CTRL0 register provides the userwith the ability to selectively enable, disable, or override the controlof individual analog circuit functions in the Tronium PSSoC to providean alternate method of control should the Control State Machine need tobe bypassed. The TEST_CTRL1 register provides the ability to multiplexinternal analog and digital signals to the ANATST and DIGTST output pinsfor test purposes.

Many modifications and variations of the present invention are possiblein light of the above teachings. The invention may be practicedotherwise than as specifically described within the scope of theappended claim.

FIG. 30 is a connection diagram that may be used with the Tronium PSSoC106.

FIGS. 31 and 32 are additional schematic illustrations of the TroniumPSSoC 106. FIG. 33 is a flow chart of an algorithm for a low-currentdetection and an error detection that may be used with the Tronium PSSoC106. FIGS. 34 and 35 are schematic illustrations of the power circuit 22including the Tronium PSSoC 106. In the illustrated embodiment, theTronium PSSoC 106 is an advanced power controller integrated circuit(IC). The Tronium PSSoC 106 and corresponding integrated Module providea low-cost, highly efficient means to convert the AC line voltagepresent at a typical home or business electrical outlet to a reducedregulated DC voltage for consumer electronic applications. Typicalapplications include, but are not limited to, charging systems forcell-phones, tablets or other handheld devices, USB power conversion,power supplies for consumer, medical and industrial devices, and manyother possible uses.

The Tronium PSSoC provides high efficiency, low noise, and low EMI withthe configurations and features as set out above. In addition, theAC-DC, DC-DC converter has high power density, low cost, and electricisolation. These advantages are achieved from integrating otherwisediscrete parts onto the chip, utilization of the Switch CapacitorsVoltage Breakdown scheme and primary side sense/control. Thus, the keyfeatures of the Tronium PSSoC are as follows: Support for wide range ofavailable AC input voltages and frequencies; Programmable Output Voltageand auto-detect of input voltage with automatic setting to configure tothe input voltage for proper operation; High-Efficiency switch capacitorcircuit for AC-DC, DC-DC Conversion; PID (or similar) Regulation ControlLoop for High Accuracy; Digital State Machines for Current andTemperature Monitoring; Ultra-Low Power Dissipation for Idle (Vampire)Mode of Operation; Opto-Isolated Microprocessor Interface forConfiguration and Control; and Communications Port for ManufacturingTest.

The analog and digital interfaces, inputs, and outputs of the TroniumPSSoC are able to withstand Voltages and Currents that are outside ofthe typical operating range. The unit is also operable over a widetemperature range and provide ample ESD immunity.

The Tronium PSSoC provides inputs and outputs to interface to theoutside world and external circuitry. These include but are not limitedto: power inputs, power outputs, low current shutdown enable inputs,mode selection input, intermediary connections for which externalcircuitry is required, test connections, communications connections,power outputs, regulator outputs, connections for PID based PWM, FETdrive outputs, and feedback inputs.

The Tronium PSSoC is an advanced power controller integrated circuitdesigned to provide output voltage regulation with high-efficiency andhigh accuracy. The advanced features of the Tronium PSSoC provide theuser with a multi-purpose device which can be used in a large variety ofapplications. Programmable output voltages are possible with the TroniumPSSoC, with little or no loss of efficiency across a variety of currentload conditions.

The Tronium PSSoC uses a proprietary switch capacitor circuit system tomaintain high-efficiency regardless of the load voltage or current. Whenno current is being drawn by the load, the device will enter alow-current mode of operation to minimize the traditional ‘vampire’current required to stay awake as well as scale the number of activesubsystems to the load in order provide high efficiencies across a wideloading range.

A top-level block diagram of the Tronium PSSoC is shown below, and iscomprised of the following major circuit blocks: High-VoltageMulti-Stage/Multi-Branch switch capacitor voltage breakdown circuit; PID(or other switched mode control scheme), Regulator Control Block for PWMControl of Secondary Transformer; Current and Temperature Sense Blocks;ADC or Comparator for Voltage and Current Monitoring; DAC, PWM, or othersignal for Feedback Control; Digital Control Block for Voltage & CurrentMonitoring State Machines; Communications Interfaces; and PowerManagement for On-Chip Voltage and Current Generation and other powerrequirements.

Power Management. The power management block provides necessary powerrails and references to the rest of the IC. It is comprised of voltageregulators, current references and voltage references. It also includesall necessary buffering and amplification needed for IC usage. The powermanagement system also contains a reset controller which manages theshut down and start up of the system on power cycle.

Switch Capacitor Voltage Breakdown Circuit. The switch capacitor voltagebreakdown circuit of the Tronium PSSoC works as a near lossless voltagedivider. It divides the rectified DC voltage present at the LINE_IN pinto a reduced voltage at the CP2_OUT pin for use by the externaltransformer and secondary voltage control loop. An external transformercan then further reduce this voltage to the desired application voltageas a function of the primary-to-secondary windings ratio, as well asprovide isolation if desired.

The switch capacitor circuit is configured as a cascade of multipleidentical stages with multiple parallel branches as shown below. Theparallel branches are switched in or out of the circuit based upon theload current that is sensed by the current sense amplifier. This enablesthe switch capacitor circuit to maintain high efficiency across the widerange of load currents. In the diagram below, the number of parallelsubsystems is 4 comprising two stages. The number of parallel systemsand conversion stages may change so that the system is best optimizedfor a particular input/output voltage ratio or power requirement.

The switch capacitor circuit uses on-chip or off-chip fly-backcapacitors to maximize power efficiency and external hold capacitors tominimize the voltage ripple. These capacitors are connected to theCP1_OUT and CP2_OUT pins, respectively, for the outputs of the 1st and2nd stages of the switch capacitor circuit. All stages are clocked by anoscillator, or each stage may have its own dedicated oscillator. Eachbranch of the switch capacitor circuit may have an independent enable.

The output voltage is programmable over the range of voltages for agiven range of applications with high resolution with the use of adigital-to-analog converter (DAC). The digital control of this DACenables multiple voltages to be programmed at the CP2_OUT pin to obtainthe desired final output voltage required for the target application.

The switch capacitor circuit output settings of the other switchcapacitor circuit stages can be determined by the user or derived fromthe measured AC line Vin, so that an optimum ratio between Vin and Voutcan be realized.

Regulation of each switch capacitor circuit stage is obtained with theuse of an Operational Trans-conductance Amplifier (OTA). The OTAregulates the current applied to the fly-back capacitors in each stageas a function of the difference between the output voltage and the inputreference voltage. The input reference voltage may be programmed,derived, or fixed depending on application.

Voltage measurement of the incoming line may be taken in order tooptimize the switch capacitor circuit settings. This setting calculationcan be performed on-chip, off-chip, or on the fly through appropriate onchip circuitry, so that the outputs of each switch capacitor circuitstage are in the most optimized ratios.

Current Sense Amplifier. The current sense amplifier in the TroniumPSSoC allows the device to measure current as part of the feedback loopas well as error reporting. The current can be measured by an ADC orthrough a series of comparators with varying thresholds.

PID Control Loop. The Tronium PSSoC provides aProportional-to-Integral-and-Differential, PID, loop or alternative PWMcontrol circuit in order to drive the primary side of the isolationtransformer, a buck, a boost, or a buck-boost circuit. This circuit isto provide post regulation and isolation if necessary.

Feedback to the PID loop can be from either a digital source forexample, but not limited to, a serialized ADC stream or an analogsignal, both of which are dependent on the output of the circuit. Thisfeedback can provide information relating regulated output current orvoltage.

Temperature Sensor. An on-board temperature sensor may be realized sothat ample protection from over temperature situations exists. Actionstaken to protect against thermal damage may include de-rating of outputpower and complete shut-down of output.

Control Circuitry. The Tronium PSSoC provides for control whetherthrough digital means or through analog circuitry. Through this controlcircuitry, the IC is able to set and change existing control thresholdsand control points as well as enable/disable specific functionality.This can be done through registers or fuses in a digital interfacesituation or through applied voltages to analog pins should analogsetting be desired.

If the feature is enabled, the Tronium PSSoC allows the output of thesystem to be disabled or de-rated. This can take place by turning offthe PWM, switch capacitor circuit, or through de-ration of either orboth subsystems. The output can be disabled as a result of errordetection or as a result of a low output current or output powersituation such as arises when a connected device that includes a batteryis done charging the battery and the Tronium PSSoC is only providingpower to the non-battery charging functionality. Once the Tronium PSSoChas entered into a low current shut-down state, it will intermittentlyre-apply output power to the end device in order to check whether or notit now requires power above certain threshold indicating that thebattery now needs further charge. The time spent in the off state may beadjusted for varying applications. FIG. 33 illustrates an example of thealgorithm for low-current detection and error detection.

The Tronium PSSoC provides multiple interfaces to external circuitry sothat devices may control and configure the IC. These interfaces caninclude, but are not limited to, SPI, I2C, UART or othersynchronous/asynchronous serial stream. Alternate encoding to NRZformats can also be realized to optimize the size and part count ofexternal circuitry. Likewise these communications interfaces can beconnected to isolation devices in order to enable communications from anisolated region should this be desired.

Clock Generator. The Tronium PSSoC may have the ability to generate itsown internal clocks which may also include frequency controllingcircuits including, but not limited to: internal RC oscillators, PLLs,FLLs, clock dividers, VCOs, and trimming circuitry. Additionally theclocking tree may implement intentional clock jitter or other means tovary the clock edge placement in order to minimize the effects of theclocking on radiated and conducted EMI.

Module Description. The Tronium PSSoC is intended for use as a powersupply device which is to be incorporated into a module which accepts ACpower in, converts this power to a DC Voltage, and supplies this powerexternal devices. The module can take many forms, which can includeeither analog or digital feedback of the output to the ASIC, or the ASICcan operate in open loop mode with no feedback. Additionally, modulecircuitry can be constructed so that individual outputs (should there bea plurality of connected outputs) can be discretely monitored andcontrolled. The sensing capabilities within the module are meant tosupplement or replace the measurements taken by ASIC depending on theapplication and regulation requirements.

FIG. 34 is a schematic of the power circuit 22 including DigitalFeedback module with isolation and discrete output sensing. FIG. 35 is aschematic illustration of the power circuit 22 including Analog Feedbackmodule with linearization of feedback isolation. These represent ananalog feedback version and a digital feedback version. Both of thesediagrams also indicate an isolation transformer as part of the design.This component may or may not be included in the module depending on therequirements of the application. Both examples describe a synchronousrectification scheme, however an asynchronous system could also berealized.

Digital Feedback Description. The digital feedback module includes amicrocontroller, standalone ADC, or secondary ASIC in order to monitorthe output voltage and to allow very precise measurements to be taken atthe output connection. This allows the module to compensate forcomponent losses, temperature, and other variables that may causevariance in the output voltage. This data is then formatted and sentback to the ASIC to provide the digital feedback stream. Current sensingand output enable transistors are also shown so that should a multitudeof outputs be connected to the module with individual sensing at each.In this manner the low power shut-off functionality described in theASIC description could be applied to individual loads even though thepower is shared.

Analog Feedback Description. If for cost or other reasons it is desiredto use an analog feedback system, the Tronium PSSoC allows this to berealized through the analog feedback input. In the embodiment shown, thecurrent through an opto-isolation LED is proportional to the outputvoltage. The circuit is designed so that the voltage at the analogfeedback pin on the IC is at nominal voltage when the output voltage isat the target output. Current monitoring is performed by the IC at theprimary side of the transformer, and the measurements are scaled by theturns ration of the transformer.

FIG. 36 is a schematic illustration of a Level Shifter circuit that maybe used with the power circuit 22. In one embodiment, the switchcapacitor voltage breakdown circuit 32 and the buck regulator 34 relieson a level shifter that can take a static CMOS level digital signal andvoltage shift the signal to various levels. This is done to properlydrive the gates of high voltage switches both off and on Tronium PSSoCchip. The level shifter is comprised of a differential pair with astatic dc current bias current. The diff pair amplifies the CMOS levelsignal and then shifts to a higher rail. There are cascodes used in thesignal path to avoid any transistor breakdown. The level shifter can bedisabled via a p-channel switch to avoid any static current drain. Oncethe signal is shifted to another rail, it is further amplified convertedto single ended and then converted back to static CMOS levels to drivehigh voltage switches.

FIGS. 38 and 39 are additional schematic illustrations of the powercircuit 22. In one embodiment, the forward converter transformer 102 mayinclude a tertiary winding 152 (shown in FIGS. 39 and 40) that may beused as a replica of the secondary side for current sensing. Forexample, some Tronium PSSoC applications can run at low voltages and aself driven synchronous rectifier may not be a reliable solution. Moregate voltage would ensure a robust system. For example there will be anapplication for a 1.8 Volt DC output. Assume a 12:1 transformer and a 43Volts CP_DAC2 setting, 3.6 VDC is the peak voltage on the secondarywinding. A 12:2 auxiliary winding can be used to produce 7.2 Volts ofgate drive for the synchronous rectifier FETs. The transformer designmay include the auxiliary winding 152 on the secondary side to supportthis requirement.

FIG. 41 is a schematic diagram of the power circuit 22 including a DC-DCconversion circuit. In the illustrated embodiment the power circuit 22includes the switch capacitor voltage breakdown circuit 32 for receivinga DC input power signal and generating a DC output power signal having alower voltage level. In one embodiment, the power circuit 22 may alsoinclude the switch-mode buck regulator 34 coupled in parallel with theSCVBC 32. The high-efficiency switch capacitor voltage breakdown circuit32 includes a pair of flyback capacitors electrically coupled inparallel, and a plurality of switch assemblies that are electricallycoupled to each of the pair of flyback capacitors. In one embodiment,the gates between the capacitors are shared. The switch assemblies maybe operated to selectively deliver an input DC power signal to each ofthe pair of flyback capacitors during a charge phase, and to selectivelydeliver an output DC power signal to an electronic device during adischarge phase that has a lower voltage level than the input DC powersignal. At least one switch assembly may include an N-channel MOSFETswitch and a level shifter for delivering a control signal to theN-channel MOSFET switch. In addition, a dickson charge pump may becoupled to the level shifter to receive the input DC power signal andgenerate an output power signal having a higher voltage level than theinput DC signal. The output power signal is delivered to the levelshifter for use in operating N-channel MOSFET switch (or closing forother types of MOSFETs). In addition, the switch capacitor voltagebreakdown circuit may include a control circuit that includes a voltagesensing circuit for sensing a voltage level of the input DC power signaland a gain controller configured to select a gain setting of the switchcapacitor voltage breakdown circuit as a function of the sensed voltagelevel and operate each of the plurality of switch assemblies as afunction of the selected gain setting.

This written description uses examples to disclose the invention,including the best mode, and also to enable any person skilled in theart to practice the invention, including making and using any devices orsystems and performing any incorporated methods. The patentable scope ofthe invention is defined by the claims, and may include other examplesthat occur to those skilled in the art. Other aspects and features ofthe invention can be obtained from a study of the drawings, thedisclosure, and the appended claims. The invention may be practicedotherwise than as specifically described within the scope of theappended claims. It should also be noted, that the steps and/orfunctions listed within the appended claims, notwithstanding the orderof which steps and/or functions are listed therein, are not limited toany specific order of operation.

Although specific features of various embodiments of the invention maybe shown in some drawings and not in others, this is for convenienceonly. In accordance with the principles of the invention, any feature ofa drawing may be referenced and/or claimed in combination with anyfeature of any other drawing.

1. An electrical circuit for providing electrical power for use inpowering electronic devices, comprising: a primary power circuit adaptedto be electrically coupled to an electrical power source, the primarypower circuit configured to receive an alternating current (AC) inputpower signal from the electrical power source and generate anintermediate direct current (DC) power signal, the intermediate DC powersignal being generated at a first voltage level that is less than avoltage level of the AC input power signal; and a secondary powercircuit electrically coupled to the primary power circuit, the secondarypower circuit configured to receive the intermediate DC power signalfrom the primary power circuit and deliver an output DC power signal toan electronic device, the output DC power signal being delivered at anoutput voltage level that is less than the first voltage level of theintermediate DC power signal.
 2. An electrical circuit in accordancewith claim 1, the primary power circuit including a rectifier circuitconfigured to receive the AC power input signal from the electricalpower source and generate a rectified DC power signal, the rectified DCpower signal having a voltage level that is approximately equal to thevoltage level of the AC input power signal.
 3. An electrical circuit inaccordance with claim 2, the rectifier circuit including a full-wavebridge rectifier.
 4. An electrical circuit in accordance with claim 2,the primary power circuit including a switch capacitor voltage breakdowncircuit coupled to the rectifier circuit for receiving the rectified DCpower signal from the rectifier circuit and generating the intermediateDC power signal.
 5. An electrical circuit in accordance with claim 4,the switch capacitor voltage breakdown circuit including: a pair offlyback capacitors electrically coupled in parallel; a plurality ofswitch assemblies electrically coupled to each of the pair of flybackcapacitors, the plurality of switch assemblies being operated between acharge phase and a discharge phase; and a hold capacitor electricallycoupled to each of the pair of flyback capacitors, the plurality ofswitch assemblies being operated to selectively deliver the rectified DCpower signal to each of the pair of flyback capacitors during the chargephase and to selectively deliver the intermediate DC power signal to thehold capacitor during the discharge phase.
 6. An electrical circuit inaccordance with claim 5, at least one of the switch assembliesincluding: a N-channel MOSFET switch; a level shifter coupled to theN-channel MOSFET switch for delivering a control signal to the N-channelMOSFET switch; and a dickson charge pump coupled to the level shifter,the dickson charge pump configured to receive the rectified DC powersignal and generate an output power signal having a voltage level thatis greater than the voltage level of the rectified DC power signal, theoutput power signal being delivered to the level shifter for use inoperating N-channel MOSFET switch.
 7. An electrical circuit inaccordance with claim 5, the switch capacitor voltage breakdown circuitincluding a control circuit coupled to each of the plurality of switchassemblies, the control circuit including: a voltage sensing circuit forsensing a voltage level of the rectified DC power signal; and a gaincontroller configured to select a gain setting of the switch capacitorvoltage breakdown circuit as a function of the sensed voltage level andoperating each of the plurality of switch assemblies as a function ofthe selected gain setting.
 8. An electrical circuit in accordance withclaim 4, the primary power circuit including a buck regulator circuitelectrically coupled in parallel with the switch capacitor voltagebreakdown circuit, the buck regulator circuit for receiving therectified DC power signal from the rectifier circuit and generating theintermediate DC power signal.
 9. An electrical circuit in accordancewith claim 8, the buck regulator circuit including a regulator switchassembly coupled to a voltage reduction circuit, the voltage reductioncircuit including a diode, an inductor, and a capacitor, the regulatorswitch assembly being operated to selectively deliver the rectified DCpower signal to the voltage reduction circuit.
 10. An electrical circuitin accordance with claim 9, the buck regulator circuit including acontrol circuit for providing a pulse-width modulated control signal tothe regulated switch assembly to selectively deliver the rectified DCpower signal to the voltage reduction circuit, the control circuitincluding: a voltage sensing circuit for sensing the first voltage levelof the intermediate DC power signal; and a regulator controller forgenerating the pulse-width modulated control signal as a function of thesensed first voltage level, the regulator controller configured toadjust a duty cycle of the control signal being delivered to maintainthe voltage level of the intermediate DC power signal at a predefinedvoltage level.
 11. An electrical circuit in accordance with claim 1, thesecondary power circuit including a forward converter circuit includinga primary voltage reduction circuit and a secondary voltage reductioncircuit, the primary voltage reduction circuit configured to receive theintermediate DC power signal from the primary power circuit and delivera secondary DC power signal to the secondary voltage reduction circuit,the secondary DC power signal having a voltage level that is less thanthe voltage level of the intermediate DC power signal, the secondaryvoltage reduction circuit configured to receive the secondary DC powersignal and generate the output DC power signal being delivered to theelectronic device.
 12. An electrical circuit in accordance with claim11, the primary voltage reduction circuit including a transformer, aprimary side of the transformer being coupled to the primary powercircuit and a secondary side of the transformer being coupled to thesecondary voltage reduction circuit.
 13. An electrical circuit inaccordance with claim 12, the secondary voltage reduction circuitincluding a pair of diodes, an inductor, and a capacitor.
 14. A powermodule for providing electrical power for use in powering electronicdevices, comprising: a rectifier circuit configured to receive an ACpower input signal from an electrical power source and generate arectified DC power signal; a switch capacitor voltage breakdown circuitand integrated circuit controller coupled to the rectifier circuit forreceiving the rectified DC power signal from the rectifier circuit, theintegrated circuit controller for sensing the voltage level of the ACpower input signal and adjusting the gain of the switch capacitorvoltage breakdown circuit as a function of the sensed voltage level togenerate an intermediate DC power signal; and a forward convertercircuit coupled to the switch capacitor voltage breakdown circuit, theforward converter circuit including a transformer for receiving theintermediate DC power signal and generating an output DC power signalbeing delivered to an electronic device.
 15. A power module inaccordance with claim 14, including a buck regulator circuitelectrically coupled in parallel with the switch capacitor voltagebreakdown circuit, the buck regulator circuit including a regulatorswitch assembly for receiving the rectified DC power signal from therectifier circuit and generating the intermediate DC power signal.
 16. Apower module in accordance with claim 15, the integrated circuitcontroller including a buck regulator control circuit for providing apulse-width modulated control signal to the regulated switch assembly.17. A power module in accordance with claim 14, the forward convertercircuit including a transformer switch assembly coupled to thetransformer primary side, the integrated circuit including a transformercontrol circuit for selectively operating the transformer switchassembly to maintain a voltage level of the output DC power signal. 18.A power module in accordance with claim 14, the switch capacitor voltagebreakdown circuit including: a pair of flyback capacitors electricallycoupled in parallel; and a plurality of switch assemblies electricallycoupled to each of the pair of flyback capacitors.
 19. A power module inaccordance with claim 18, at least one of the switch assembliesincluding: a N-channel MOSFET switch; and a dickson charge pump coupledto the N-channel MOSFET switch.
 20. A power module in accordance withclaim 18, wherein the N-channel MOSFET is formed within the integratedcircuit.